[aaronbaugher]

Yeah, as long as you pay reliably (ideally automatically) so you never get hit with any fees, it's fine.

But if everyone did that, these companies would go out of business. So they're clearly counting on a significant percentage of users failing to do that, and sticking themselves with the fees in the fine print. And those tend to be the folks who can less afford it and are less equipped to reliably handle such things, making the enterprise feel predatory.

[SirMaster]

Would they go out of business? They make a % of every transaction too.

What % of a credit card companies income is transaction fees vs account interest?

I would argue that a credit card company could probably operate on transaction fees alone. Sure they might need to downsize, but I think the transaction fee would be enough to pay for the minimum infrastructure to run such a company providing the service they provide.