The local shop I go to seems to encourage payment by card even when it's for less than a tenner.I've noticed their prices slowly creeping up in the last few months on the basic stuff.Milk, bread etc.Only 20 cent extra on a few things but they're obviously factoring in the card fees for the cash purchases too.So they win on every purchase.
One takeaway near me still puts the 30cent extra on for card payments.Nobody seems to give a bollox so they'll keep doing it.