It isn't just related to the small shop either. The dealerships get right into the mix with their dishonesty. I think, especially if you are out of town and they don't expect you to come back.
I was out of town, but only by a couple of hours. My Suburban shut down and wouldn't restart. It only had about 15,000 miles on it and had always been properly maintained. I called the Chevy place for a tow and when they had a look at it in the shop, they told me the engine was seized up and that there was no oil in it at all. They did have a replacement and could install it and have me on the road in a few hours for only $3500. It wouldn't come under warranty because they had found no oil in the engine.
I called my local Chevy dealer to come pick it up and bring me a loaner. My dealer found that the engine was missing the alternator belt. Nothing else was wrong including the oil level.
This kind of stuff is very commonplace even in large dealerships. Lithia.