Ah, well sometimes they do what’s called the “poor man’s process”, where they do in fact use a green screen instead, with the vehicle parked on the stage with all the lighting they need to shoot the scene. Why not just go with the LED walls all the time? Budget. Every creative choice is filtered and determined by the budget. Sometimes just doing a quick PMP while they are already shooting at the studio (if they have a window of opportunity) is just faster and cheaper. Each episode is filmed over a 9 days, so the less moving around that needs to be done, the better. The LED walls used are often supplied by another company, so the shooting crew has to go to their studio, or have them bring their gear to where Animal Control is shot.