Oh and it also depends on what teaching materials he's using.
I wouldn't pay anybody $75/hr (or even $50/hr) if they didn't have useful, informative, and up-to-date information to disseminate... preferably displayed with modern equipment.
If dude is using presentation equipment (projectors, laptop, etc.) and distributes color-copies or professionally-bound booklets, and things like that... he puts money into his business, and probably deserves to get it back.