Why couldn't he have taken down your credit card info and wrote up a reciept for you? Thats something that would take less than 5 minutes a very simple solution and would have had you on your way. Hopefully for their sake they realize they didn't treat you very well in this instance and offer you something to keep you coming back like a discount or accessories like other posters have mentioned. Word of mouth is the best/worst form of advertisement and for a few bucks he could keep you as a customer and you will also not steer people away from them. Some business owners don't get that concept though which isn't surprising in the moment I guess.

If you decide to leave maybe its time to spend the few dollars on the tools to work on your bike. They don't take up much space at all (you don't need a workstand) and don't cost much either. Of course I am sure some other LBS would be happy to have your business as well which would be great.