The flight simulators are expensive to maintain. Hydraulics + vibration platform, computers, visual system, software, annual certification, the air conditioned facility that it's contained in, plus the spare parts inventory. There are many specialist engineering and maintenance staff required, flight instructors, support and admin staff etc. The initial capital outlay is about that of the real aircraft also. Add up all these costs, plus the cost of the finance to pay for it all, and divide that by the annual revenue hours, and you'll find there isn't much profit margin built into the client chargeable rate.