I've worked with some really bad mechanics out there. Some real good ones too, but when there is money to be made easily, it seems like morals go out the window.
One guy would get a car in for an alignment. He'd drive it down the road. If the steering wheel was centered and it didn't pull, he called it good. Never even drove it up on the alignment rack. Spend 2 minutes on a test drive and charge the customer an hour and half.