Shoppers in grocery-branded forecourt stores - such as Budgens and Sainsbury’s Local - spend 75% more than in oil company-branded stores, according to shopper research specialist HIM in its latest Convenience Tracking Programme report.

Director Tom Fender said: "Oil company shoppers spend £4.13 per trip while grocery forecourt shoppers spend £7.23.

"However, it’s important to realise that the oil company shoppers only intended to spend £3.80 while the grocery forecourt shoppers intended to spend £8.22. So the grocery outlets missed out on £1 per shopping trip."

There were also marked differences in the types of items purchased. In oil company stores, it’s all about impulse lines such as confectionery, soft drinks and snacks, while in grocery forecourts there was much more emphasis on food, and particularly on fresh lines.

Said Fender: "Grocery forecourt shops are being used much more as local convenience stores, with 50% of shoppers saying they are a convenient alternative to a supermarket. Plus 43% of grocery forecourt shoppers walked to the store compared to just 12% of oil company store shoppers."

Visitor frequency is higher at grocery forecourts, at 3.1 times per week, versus 1.8 visits to oil company stores.

Grocery forecourts also received better marks for shopper satisfaction for things like staff friendliness, cleanliness, fresh products and value.

Finally, 70% of grocery forecourt shoppers said they felt valued as a customer against 63% of oil company customers.