On the contrary, I think the "entitled" mindset is those business people who think their entitled to reduced competition or special treatment just because they're in business. There's no union for business owners.
It's business. It's competition. It's about giving the customers what they want. I deal with clients every day, and you don't win business by talking down to your customers or beating up on your subs. You win business by giving the customers what they want - at a better price, better service, or with better quality.
And no, the original poster was not a "sub" of the gun store owner. Not at all. He was a potential customer who was lost. If you think I'm wrong, consider that the gun store owner got a call from this potential customer and offered to buy a product. Instead of making a sale, the gun store owner decided to teach him a lesson on "good manners." I'm sure that did wonders for the gun store owner's ego, and it sounds like all of you would get satisfaction in doing the same thing.
But at the end of the day, the sale was lost. And I wonder if the OP will ever go there again - for another gun, ammo, or anything other reason.
Again, the "I'm going to get on my high horse and tell the customers how it works" mentality is incompatible with a service business. Tell me I'm wrong, but you can't argue with the bottom line - sale lost.