If you think about it, it does not make financial sense for them to maintain this kind of system as a purely progressive price discrimination that charges richer people more money. I expect a lot of it would end up more like the Uber practice of charging more to people with low phone battery; they will identify who is more desperate, who has less choice but to buy the given product immediately, and charge them more. Because of how poverty works, that's more likely the poor.

This is a major reason we still need cash and other ways of saying no to corporate surveillance; if we can't maintain privacy when making purchases that information will be used as a weapon against us.