How motorway service stations push up prices IAM chief executive Simon Best said: "Motorway Service Areas are supposed to be for motorists to eat, drink and freshen up. It's very important to have a break every two hours and these costs will put people off stopping. Tired motorists pose a danger to themselves and other road users. The cost of fuel is also much higher when bought on the motorway than it is elsewhere. The research showed that from one Motorway Service Area to the next, the price of petrol can vary by up to 10p per litre. Hopwood Park, located on the M4, charge 12 pence more per litre than the nearest off-motorway petrol station. Hopwood Park is operated by Welcome Break, one of the largest owners of motorway services in the UK. It has said that it operates as a "travel retail and hospitality business" making it unfair to compare its prices to those of a supermarket. "A more relevant comparison would be an airport, railway station or department store restaurant, where our prices would compare favourably," it said. " In setting our prices, we have to consider that we provide a large number of services 24 hours and for every day of the year. This is an expensive cost to us. The IAM is calling for a full review of motorway prices. In France, filling stations are forced to advertise their competitor's fuel prices alongside their own, and the IAM would like to see a similar policy in the UK. High petrol prices will put people off filling up. Forcing stations to advertise their competitors" prices would drive costs down." The high rent being charged on their buildings is often cited by owners of motorway service areas as the major cause of steep prices. More and more stations also now remain open 24 hours a day, the running costs of which are passed on to customers.