It's too bad some people have to be assholes but a few are just born that way. If he told you a snubby performed better than 9MM Auto he is very misinformed. I have a .357 snubby and 9MM M&P plus a chronograph. The 9MM and .357 bullets are essentialy equal, .355 vs. .357 dia., and you have to use fullhouse .357 loads in a 2" snubby to equal the performance of a 9MM auto with 5" barrel. My chronograph has proven that to me on numerous occasions.
Anyway, don't quit going to shows just try to pick the AH's out earlier and ignore them. If you can't ignore them then tell them where to get off.
Bottom line: Enjoy being a gun nut.