Banks get rich off those, or the card network, cant remember precisely. A lot of local businesses around here will give you 'cash discount.'
banks make money off them but they don't get rich
the card networks don't exactly get rich since they don't see any of your interest fees, the only thing that funds visa and it's network are those merchant fees. same with mastercard. amex and discover operate differently because they run their own networks and financial institutions
I've yet to see any place that's ever given a discount for using cash only, which is why virtually every purchase I make is with a credit card