People getting defensive at car shows!

I can relate - just went to a car show / swap meet here in Wisconsin (Jefferson). Looking at the cars, and came upon an AMC Rebel (The Machine). Complimented the guy on what a nice car it was, then asked if it was real. He went off - he went on about how of course it was, and he cannot stand people that build clones, etc. I just started to walk away during his rant, then he kind of caught up to me, and calmly apologized, I listened as he showed me more of the car. Probably talked to him another ten minutes or so.
My boys and I go to that show twice a year. We were sitting on a bench on Sunday and a guy was sitting behind his car. Another car came in and was backing up too close to his. He was going ape **** on the guy... haha we had a good laugh.