So many of you focus on the innertube and not the customer service. The OP's point relates to the poor service. The shop's lack of recognizing a long-standing customer (and perhaps extending some goodwill with a replacement tube) sits at the core of the issue. We all experienced poor service to some degree. Going back just to keep them in business seems entirely foolish.
Speaking of "buying locally," do y'all do that with all your small hardware, clothing, shoe, and tiny food markets, as well? Or on a big-ticket item like a car...do you patronize the local dealer and pay a grand more than the mega-dealer in the next city over? I suppose it's your hard-earned money to spend however you choose.