It also means stratifying card users, even if you actually make all the card users pay more than those with cash. The people who can just barely qualify for a card are paying to fund the "rewards" for the wealthy who pick the best options.

"It's expensive to be poor" is a more or less universal experience under capitalism and it's amazing how many novel ways we've come up with to make it more expensive for poor people.

"Means testing" is one of the fun ones. The wealthy will often justify this as "People like me shouldn't get this help" which sounds even generous, and then you realise, oh, because we're testing if you're worthy to receive help now to get help you need to expend some time and effort to pass the test. When this "I shouldn't get benefits" is offered to you as a reason to means test, ask them why they're taking a benefit they don't think they should have and why they can't pay society back in other ways rather than inflict more misery on the poor...