It doesn’t matter if credit card providers are paid 0%, 3% or 5% on each transaction. If the law (and/or customer blowback) allows a company to sell customer information, management will eventually give in to selling it because it’s a revenue source. When called on this they will give you a story about how it “lowers customer costs” and some people will accept this as a valid excuse, but none of this changes the reality.

PS: this is really a response to grandparent poster, not parent.