Three cans with pull tabs
Why Is Only Some Canned Food Equipped With Easy Pull Tabs?
By Haldan Kirsch
Pull tabs for canned goods are more challenging and expensive than the standard seamless seal because the lid and the tab are manufactured separately before being riveted together.
Scoring the opening on a can takes a lot of engineering, too. Soda or beer cans need a pressurized environment that can withstand temperature changes without rupturing the can.
It must be strong enough not to burst open but weak enough to open it easily. The same can be applied to food cans, but the cost of riveting the tab to the lid isn't worth it.
Although it's more convenient for customers, some companies aren't willing to raise their prices and deal with the extra manufacturing complications for pull tab lids.