People getting defensive at car shows!

It's called being courteous......has that too been lost?
At the race track = I invite the kids to sit in our race cars and find time
to chat with everyone that comes in our pits for at least a moment.
However, If people come up and start to touch and handle my cars with
I have been working on (Some for last 50 years) --We then have a Problem.
Another thing I hate is when people ***** and tell me that I ruined a
H Code Sunroof 340 4 speed car with AC and shame on me!
Well 40+ years it was not a collectible when it became a race car.