Many stations around here - Long Island NY - post prices (on the signs you can see as you drive by) that only apply for cash. At the pump, there’s often 10 cents extra (per gallon) for credit. About 2/3’rds of stations around here do this. I get all my gas at a station that posts a separate credit and cash that happen to be the same. They’ll lose my business if they ever change it.
ETA: 10 cents extra per gallon