Earlier this week, in Horsham, Sussex, you could pay anything between 136.9p and 140.9p a litre, according to figures from the UK motoring group the AA, while about 10 miles away in Crawley, prices were between 128.9p and 131.9p. There are Sainsbury’s, Tesco and Shell garages in both places, and all were charging less in Crawley. Sainsbury’s, for example, was charging 8p less – a difference of £4.40 on a typical 55-litre tank.