[folbec]

"- merchant checks if debit or credit card is accepted by their payment processor —> if not accepted, tell buyer present diff card or “get bent”"

This is america, in France (and more generally in Europe) all credit / payments cards are standardized thru governmental intervention. Vendors are allowed to say cash only and refuse cards in general but this is getting real rare. In some countries (Norway), you can have a real hard time paying cash in big cities, vendors refuse it.