Ah, but you are not the owner. He can run his business in the manner he chooses. When you have a business you can run it as you choose.
The key is, if you do not like how a business conducts commerce, take your money to another vendor. I don't think you are a b.... just that you are a bit overwrought. I've worked in retail and I recognize certain customers are "high maintenance". Such customers may quickly become too much trouble for too little money. "The customer is always right . . . most of the time."
I haven't seen any damage or loss presented on your part. If there was, members have offered good suggestions for recovering such.