(Offtopic) credit card charges

I don't own a credit card, so they might be different, but debit card charges are usually hidden by large retailers, but added to the bill by smaller retailers. Eg. using a debit card at my local pub incurs a charge of 75 pence (actually they may well not accept credit cards at all).

I suppose larger retailers can get better rates, and see greater value in charging everyone the same, whereas a smaller retailer would have to increase their prices by a large enough fraction to risk losing cash customers if they charged everyone the same.