> But CCs do charge 1-5% to the seller for the initial ~30 day loan period
Are you talking about the balance transfer? I'm looking at this credit card ad from Bank of America and the only time it mentions a 1-5% initial fee is if you apply for their card and then transfer a balance-due from an old credit card to the new one:
https://www.bankofamerica.com/credit-cards/
I also asked an LLM if credit cards charge interest to the seller for the initial loan period, and it says no
