I would question this personally, certain "flight schools" seem to use anything over and above what is considered a regular lesson to charge an extortionate amount of money.
My C170a for my CPL (undertaken at a reputable UK school) was charged at the standard rate (amazing how they managed to do this while some C170a examiners run up such huge expenses maintaining the privilege).
It took 1 1/2 hours of flying and half hour of briefing and 5 minutes to complete the form. That would make it approx an additional £50 an hour for the tester on top of their wage if i had paid an further £100. That's more then alot of jet captain's earn an hour.
Buyer beware, this sort of charging is particually common with foreign JAA schools, where they hold a captive audience who have a high buy out penalty if they are not happy with their treatment.