A couple of the techs in the Goodyear shop here made close to six figures witrh the way they do double time and triple time. Don't know of any one else even coming close. Who absorbs the overtime chargres, the customer? The ones around here would run you off for charging overtime rates.
While working a lot and making money is ok, there is a lot more to life than money. I'd rather have the time off to ride my scoot and enjoy my family.
If I caught someone billing 8 hrs for 3 hrs work, I'd probably skin them myself.