In Roger Corman's autobiography, he talks a little bit about the few big studio films he made. He says that, in many cases, the amount of labor costs attributed to a film would have absolutely no bearing on reality. For example, he would need, say, 3 Teamsters to move some lumber from one end of the studio lot to the other. Then, the studio employs, say, 20 Teamsters on its lot full time. 15 of them are occupied working on other movies. That leaves 5 available to move the lumber. Only 3 are needed for the job but the studio charges the time of all 5 of them to Corman's movie. That way, they inflate the budget of the movie and make it look like all of their full time Teamsters are occupied.