They… kind of sort of already have.

You can just throw money into your Steam account, via the mechanism they came up with for Steam Gift cards.

So, buy a physical gift card, or just give Steam your bank/card info, take money out of bank, give to your Steam Gift balance.

So uh, presumably, that Steam Gift Balance doesn’t exist in a bank anymore, beyond being a withdrawl from your account, its now just … a $USD value associated with your Steam account, that you csn now buy anything with, and your original bank/card company has no visibility into that second transaction.

So… they could theoretically use what I just described above as a ‘workaround’, you just make the offending games only purchaseable via goon gift balance.