12 Things You Should Avoid Buying At Costco

Costco isn't the only warehouse store out there, but the continuously growing chain's members are fiercely loyal. According to Zippia, from 2011 to 2021, Costco's revenue increased from $87 billion a year to nearly $200 billion — that's more than double in only 10 years. People who pay the yearly membership fee and deal with the crowds (which are worse on weekends) snap up bargains on a dizzying array of products.

Buying in bulk has its good and bad points, according to FinanceBuzz. If you own a company or have a large family, it's worth it because you'll make up the membership fee in savings. Just as importantly, the products won't sit in your home or business for months because they're not getting used up. Costco also has its own gas stations, sells pet products, and offers services like eye exams. You can get a lot accomplished in one visit, but it could take you hours to get finished — this is not like a quick trip into the grocery store. FinanceBuzz notes that not everything you find at Costco is a good deal, though, and recommends comparing prices at other retailers instead of just grabbing things from the shelves.

Those oversized Costco shopping carts are designed to be loaded up, and temptation is everywhere. But besides not always having the best deals, some of Costco's goods might be lacking in other areas.

1. Fresh fruits and vegetables

Everything at Costco is sold in bulk, so instead of buying four apples or oranges, you might have to get a whole bagful. We're all about eating healthy, but one can only eat so many fruits and veggies in one day. The American Heart Association recommends four servings of fruit and five servings of vegetables per day. One serving might be ½ cup of arugula, ¼ cup of fruit juice, or a medium-sized apple — not three at a time. So if you or your family won't finish 15 bananas in a week, you might have to throw the extras out. You might have longer with other fruits, but bananas don't last as long.

The USDA notes that most produce cannot be stored at room temperature for too long and must be put in the fridge. That's why people with smaller families don't usually buy fruits and veggies in bulk at grocery stores. As for quality, Costco's produce is acceptable or better, but it can't compare to farmers markets. That's where you'll find the freshest, locally grown fruits and vegetables. Since things are grown close to the selling points, it's much fresher than produce that travels for hundreds or thousands of miles. Farmers markets also sell peak-season produce and have cool stuff like gooseberries or ears of corn chilling in ice buckets.

2. Candy

Costco sells bagged candy, and these bags are perfect for trick-or-treaters and classroom parties but not sitting in your pantry; is it a good idea to have tons of candy in your house? Harvard Health Publishing states that natural sugars in fruits, veggies, dairy, and grains are healthier, but added sugar is problematic. Excessive consumption can lead to diabetes, heart problems, and other serious medical issues. Americans get added sugar from cakes and candy, but foods like ketchup, bread, and soups also contain it — you'll be amazed when you read how many grams of sugar things like barbecue sauce have, too.

Instead of treating yourself to a single candy bar, you'll end up buying a whole bag of them at Costco. You can buy individual candy bars and smaller bags at grocery stores. And while no one can deny the pure pleasure of a chocolatey Kit Kat bar or tangy Sour Patch Kids, those can get old after a while. If you're going to splurge, stop by an actual candy store for a better variety. You'll also have more control over the amount purchased.

3. Designer clothes

Consumers are drawn to designer clothing, and while Costco has well-known brands like DKNY, you're not necessarily getting the same quality as in department stores. Budget Fashionista states that Costco sells DKNY hoodies for $24.99 and Polo Jeans T-shirts for $9.97, but their quality is likely not as great. It'd be a better idea to shop for them at department stores that carry the brands; just wait until they go on sale to get the best deals. Also, Costco does not have fitting rooms, so if something doesn't look or feel right when you try it on at home, you'll have to bring it back to the store. That is unless you're brave enough to try on clothes in the middle of a store with all those people watching. No thanks.

According to CBC, outlet stores can have authentic designer goods, but these are also different from what brand retail stores have in stock. Back in the day, retailers used outlet stores to sell overstock and factory seconds, but now, they manufacture separate lines to sell. So just like Costco, you won't be getting incredible prices on authentic, top-quality designer duds. Clark points out that Costco has its own Kirkland clothing line and only marks the items up by 15%. The quality is comparable to the chain's so-called designer offerings, and you can scoop up good deals on basics like T-shirts, socks, and underwear.

4. Milk

Unless you have a large family that consumes a few gallons of milk per week, steer clear of Costco's refrigerated milk section. The containers are bulky and heavier than what you see in grocery stores, and you could end up wasting much of what's inside them. And what if you prefer 1% milk, your partner likes unsweetened almond milk, and your kids refuse to drink anything else but whole milk? You see where we're going with this. Grocery stores usually have the largest selections of milk, and you'll be able to please everyone without buying multiple oversized jugs.

But no matter where you buy your milk from, check those expiration dates first. Medical News Today explains that most milk in the U.S. is pasteurized and shows expiration dates. Have you ever drunk milk that was well past that date? We have, and it's not pretty, especially when you see just how far past that date is. Stored milk generally lasts five to seven days after the printed date, but other milk (including lactose-free) stays fresh longer.

A giant jug of milk can easily be unfinished before it expires. But if you have a lot of still-fresh leftover Costco milk, don't pour it down the drain, because there are a lot of great recipes that use a good bit of milk. Examples include potato gratin, pancakes, mac and cheese, and, hooray, milkshakes!

5. Books

Like much of the clothing it sells, Costco's book selection is constantly changing. If you search for search fiction books on its website, you'll notice a lot of boxed sets for children and young adults, but not as many single copies. Other genres include nonfiction, cookbooks, and reference books. You'll find more choices (including single copies) inside the stores, but if you're looking for a particular read, it might not be in stock.

The future of Costco's book departments also seems unclear. In an October 2022 issue of Honolulu Civil Beat, Denby Fawcett wrote that the warehouse chain stopped selling books in all seven of its Hawaii locations. She added that Costco would no longer be selling books in that state or Alaska. Fawcett also claimed that besides independent bookstores, Barnes & Noble was the only large bookstore chain left on the islands.

Of course, you can still order books online, but sometimes it's nice to browse in a locally owned bookstore even if you have to pay a bit more. Used book stores can also have great selections, but if you don't have any of either nearby, turn to your local library. If you have a Kindle, you can also borrow books for free through the OverDrive app. The last three choices are the most sustainable ones, BTW.

6. Toilet paper

Predictions of bad weather and pandemics lead to toilet paper shortages and price gouging at retailers, and we all saw this happening at stores in 2020. Dr. Ronalds Gonzalez tells NC State University College of Natural Resources News that supply chain issues are not the problem; TP shortages are caused by panic buying and hoarding. Now that supplies are back to normal, we have the luxury of comparison price shopping for toilet paper. According to Living on a Dime to Grow Rich, the best way to do this is to check the number of sheets per roll and cost per sheet: The price might be the same for 24 rolls of Charmin and Scott, but you might be getting fewer sheets in one of the packages.

The Ascent notes that inflation has kept costs high in recent years but claims that Walmart's prices for non-grocery items like toilet paper can compete with Costco's. They also make a good point that if Walmart is closer to your house than Costco or vice versa, you'll save gas on whichever store is the shorter drive. Walmart's selection of non-grocery items might be more extensive, but if you need a ton of TP, Costco sells a few brands in units of 96 rolls. This is a good buy if you own a business or have a large family. Otherwise, you might pay more and not have enough room in your house to store all those extra rolls.

7. Diapers

New parents know how expensive diapers can be and are always looking for ways to save money on them. More Perfect Union explains that Kimberly-Clark and Procter & Gamble (P&G) almost have a monopoly on the diaper industry — their Huggies, Pampers, and other brands make up close to 80% of the market. In 2022, Parents Together Action claimed that diaper prices had increased by 22% since 2018 and accused P&G of price gouging. Meanwhile, More Perfect Union reports that a box of 168 Pampers at Walmart cost about $60 in 2022. How does that compare to Costco?

It doesn't.

Passionate Penny Pincher posts that Costco does not sell Pampers diapers, and we couldn't find any on the website either. There's a good reason for this, according to RV and Playa. Costco sells Kirkland diapers and wipes, and guess what company these are manufactured by? Kimberly-Clark. This company also makes Huggies, the other main diaper brand that Costco sells. That's P&G's main competitor. There might be a few other lesser-known brands, but without Pampers, the selection is limited. And as for the prices, Motherhood Community posts that the best online diaper deals are found in this order: Amazon, Walmart, Costco.

8. Soda

Costco sells soda in large boxes, and since unopened cans don't need to be refrigerated, you can store them in your basement or garage. However, while buying soda in bulk can work for businesses and for parties, it's not a good idea to drink the fizzy stuff too often. 

Delta Dental explains that, like many things, soda isn't healthy when consumed in excessive amounts. Soda has no essential nutrients, and the health hazards of excessive sugar have already been explained. On top of that, the bacteria that live in our mouths interact with sugar and produce acid. That stuff just sits on your teeth — yuck. Diet soda can be bad, too, since it contains acids that can damage tooth enamel. Penn Medicine adds that diet soda may also increase your risk of heart problems, can increase the chance of stroke, and, despite the lack of sugar, has been linked to type 2 diabetes. So, if you must drink soda, try one of Costco's flavored seltzer or unsweetened iced tea brands.

9. Over-the-counter pain medications

In a YouTube video, Dr. Christy Risinger, M.D., shows that Costco sells large bottles of Advil, Tylenol, and Aleve. She explains that some of the painkillers sold there can be NSAIDs (non-steroidal, anti-inflammatory), like Advil and Aleve. These last longer but, when taken in excess, can lead to health problems like stomach damage and elevated blood pressure. She doesn't recommend NSAIDS for people over 65. Acetaminophen (Tylenol) won't cause those same side effects and doesn't need to be taken as often, but it can be less effective on inflammation.

Costco also sells oversized containers of aspirin, Kirkland ibuprofen and acetaminophen, Excedrin, Motrin, and Kirkland Signature Naproxen. According to the U.K.'s National Health Service, naproxen is another NSAID, and you may know that it's the generic name for Aleve. While Costco's prices for over-the-counter medications can be competitive, do you really need a bottle of 360 Advil pills? With such a large bottle, people can get into the habit of taking more than they need.

Overusing these pain medications can cause serious health risks, according to Silver Pines Treatment Center. Possible side effects of taking too much (including acetaminophen and aspirin) include ulcers, internal stomach bleeding, kidney and liver problems, and high blood pressure.

10. Cereal

Costco sells well-known cereals like Special K, Frosted Flakes, and Cheerios, but you won't find as big of a selection as you will at grocery stores. So if you must have Kashi, Fiber One, or Cap'n Crunch's Crunch Berries, you might be out of luck. When you do find what you're looking for, the double box often contains two bags inside, in larger sizes than the single boxes found in other stores. It's hard to compare the prices unless you check the cost per ounce. Looking at Special K with Strawberries, Costco's is 28 cents, and Walmart's is 27.7.

No, that's not a big difference, and it shouldn't affect this particular buying decision. But what if you're the only one in your house that eats this cereal, and you don't have it every day? Cereal gets stale pretty fast, and you might end up tossing it. And if you get one of the combo packs, the other flavor(s) might not be as appealing as your favorite. We prefer grocery stores because of the better cereal selection and smaller packaging. Just wait until they go on sale and use coupons whenever possible.

11. Kirkland Signature Strawberry Margarita

Costco stores that sell beer, wine, and hard alcohol have selections that rival small liquor stores. You'll find plenty of Kirkland brand products here, along with well- and lesser-known brand names. One Kirkland liquor to avoid is the Kirkland Signature Strawberry Margarita. This pre-mixed margarita contains 12.7% alcohol, and that's about the average content in wine (via BinWise). However, a reviewer on Costcuisine posted that the bright reddish pink drink was overly sweet and didn't have enough of a tequila flavor; she claimed that it had an artificial taste. Other Costco shoppers felt that the drink wasn't that good or preferred the brand's lemon-flavored version.

Kirkland Signature Strawberry Margarita is made with gold tequila, triple sec, and real lime juice. As for the artificial, too-sweet taste, that might be coming from agave wine, according to Costco Buys. This drink also contains FD&C (Federal Food, Drug, and Cosmetic Act)-recognized food colorings, and according to the FDA, these kinds of color additives are not generally recognized as safe. So if you have a hankering for strawberry margaritas, try Kirkland's classic margarita instead or make your own strawberry margaritas with fresh or frozen pureed strawberries. Still too sweet? Just make a plain margarita with tequila, triple sec, and lime juice.

12. Beef

Costco's meat department has every cut of beef imaginable, but if you see the phrase "blade-tenderized" on the label, go ahead and skip the beef. What's the problem? The USDA explains that blade-tenderized (also called mechanically tenderized or needled) beef gets poked with sharp mechanical blades or needles. This process is used to break up muscle fibers in cuts that are less tender. You might do this at home, but you can't control what happens when blade-tenderizing is done at manufacturing plants, stores, and butchers.

These meats look the same as un-blade-tenderized versions, but the USDA warns that this kind of tenderizing could be hazardous to one's health. The outside of the beef could contain bacteria that ends up inside the meat during the process. And on top of that, the equipment must be properly sanitized, or bacteria from one piece of meat could get transferred to another.

Cooking the beef to the proper internal temperature (a minimum of 145 degrees Fahrenheit) can kill the bacteria, but why mess around? If the Costco label shows that the beef was blade-tenderized, look for others that were not — you can tenderize it at home with a meat mallet or a sharp knife. Too much work? Make it a meat-free night.