I think there's a fourth class (to the third class another commenter mentions) that you're missing here, which the credit card example makes obvious: people who fall for the "human behavior" trick the company aims for, and are exploited or hurt by those practices.

Credit card case: people prone to overspending and falling in a debt loop, lured in by $500 due to being poor or in precarious situation (perhaps from falling in similar traps in the past), and who end up keeping the card long-term, as the 3-months spending requirement ends up trapping them in the CC spending loop.

This equilibrium you describe, is in many cases built on preying on the weakest and most vulnerable, so no, I don't think it's fine.

You're forgetting about the third class of person, who thinks it's not worth their time, and, frankly, distasteful to spend that much time and effort optimizing, but also finds the offers presented to those that aren't optimizing insultingly poor value.

That's the kind of person that will not download the app to get the coupons and hunt for the good deals at Safeway, but will also not accept the exceptionally high sticker price, and instead will go shop at another store.