This situation is weird.
Personally, I would contact the owner. It might actually be his policy but they need to get customer feed back.
At first, I was going to say it sounds like "Detroit syndrome", drawing parallels with "stealership" practices for automobiles. Then it struck me, even with auto dealers, you can go to any dealership parts department and buy the parts for your car. You do not need to go through the service department to get your parts installed.
Yours is an LBS which will not be around very long.