Petrol stations seem to be mini supermarkets these days. There's a petrol station in West Cork that sells pasties. Just like those we use to eat when went on holiday to Cornwall. We often stop off at petrol station for a breakfast roll. But you don't attempt to buy food on a Sunday. All you get is:
"We don't sell food on a Sunday."
Is Little Chef still open in Blighty? I don't think there aren't enough service stations here in Ireland.