I think setting up a few Flying J franchises in UK could be a money maker. I'm not a truck driver, but use them for fuel stops and meals on the road and to use the free WiFi. Pretty much as Mortblanc describes. A national chain along the major Interstates. The retirees driving RVs love them. Have pumping station for your sewage tank also, as well as free potable water and compressed air. Denny's restaurant, Subway take out sandwiches and Duncan doughnuts and coffee all under one roof, plus basic groceries and truck/auto supplies. Least expensive fuel in 100km radius.
Got one 5 miles from the house.
They are the cheapest place to fill one's propane tanks in my area too. $9 for a 20 pound tank.
They are also a good place to snag 12v appliances that plug into the power outlet on the vehicle, 12v coffee makers, kettles, skillets and even 12v microwaves.
Mine is also the best CB shop in the area.
A second home for a tired and hungry driver. There are probably 200 trucks parked outside that place every night. No charge for overnight parking. Drivers can only log 10 hours and there is a check point/weigh station a couple of miles down the road, so drivers that have their limit in can stop for a 6 hour required break before hitting the government check point. Every one of those drivers will buy a meal, pick up snacks, take a shower, catch a nap or watch a movie in the driver's lounge (no auto drivers allowed) and they will spend from $20 to $2,000 before hitting the road again.
Oh yes, they have unlimited water for bottle filling too!