There's a local Mr. Lube I go to regularly, I've had nothing but good experiences with them - although they're not cheap, a basic oil/filter change with tax, enviro fees etc. included is around CAN$50. You stay in the car, I don't think it's ever taken more than about 10 minutes.

One way to avoid the unnecessary stuff (if you do your own basic maintenance) is to ask for "no checks" up front. If you do that, they cannot open up your air filter, transmission oil dipstick etc. - you're instructing them not to do so.

My dad had one bad experience with another Mr. Lube in another suburb of Vancouver. He had just bought a new Subaru Impreza, and during his first oil change with that car the franchise checked the rear differential fluid level but didn't screw the plug back in afterwards. As he drove away the differential leaked HP oil onto his hot exhaust/muffler, generating copious noxious-smelling smoke. Fortunately, by the time he noticed this and got it back to the franchise, the differential hadn't yet run dry. If it had... as it was, it took more than a week for the noxious fumes to stop coming off the exhaust system whenever he stopped the car. HP oil is nasty-smelling stuff even without burning it.

My vote for most repugnant business would be the payday loans racket.