And keep that consumer chin up in the follow thru and don't cry like a cry baby when occasionally a store treats you like a leper trying to get it through your head that they don't want your business and to g.t.f.o.
As long as you'll take the abuse like a man and not cry or whine or post wondering why you were treated that way, I think that's fare.
As it's your prerogative to whom you will do business with it's a two way street and the dive shop owner gets the same prerogative.
No kidding. I flatly refuse to deal with people who shop or compete on price (in diving or in my profession). I'll discuss any number of other things, but things cost what they cost for a reason (or a number of reasons, none of which are really any of the customers' business). If you're unhappy with what things cost then shake my hand and walk away. If I'm unhappy with what you can afford, I'll smile, shake your hand and walk away.
The OP's shop owner is guilty of not walking away in a respectable manner. He could have said that he didn't believe in the type of diving that the OP was asking him to provide equipment for and withdrawn from the deal on "moral" grounds rather than acting like a jackass.
Though, I am willing to bet that dealing with enough nickel rockets and know it alls was the real reason for the attitude. Bad customers are as pervasive as bad vendors (if not more).