Most of these vendors do not realize that it’s good business to keep you happy. When you had a ligitimate gripe, he should have made good just to keep his good name.
When you tell people that a vendor treated you right, they tend to use that vendor. It surely wasn’t worth losing you as a customer and you telling others about your bad experience for the $70 he made.
It’s a shame, but the car hobby is rampant with predatory vendors. Some even align themselves with various car clubs to try and guarantee victims. I’d make it a point to let Black Gold know you have his number and be sure to tell all the people that are his potential customers about your experience.