A common combination in the racing community is the hospitality center, a large luxurious motorcoach pulling a kitchen trailer. A similar combination is a crew support motorcoach (might include showers and bunks) pulling a kitchen.
Neither is used as a RV, in the recreational sense, they are moved without occupants from race site to race site, where they are set up for the people who will use them on site.
Moving the race cars, moving the on-track team members, are separate operations and schedules from moving these infield support vehicles. Race cars for the next race may be on the way to the next site while the current race is still in practice, and this week's cars will be hauled back to the shop after the race, to be rebuilt. Track personnel are on much tighter schedules, and will often move by chartered air, even if they have (in the case of drivers and management) personal "RVs" to live in at the track. Sometimes even the race cars move by air, depending on the distance to travel.
So "where do they stay?" Enroute, probably at truck stops, or motel parking lots, if the schedules are such that the drivers have time for, and need for, overnight stops between the sites where the vehicles are use.
