The closest I can think of was a few months ago when I was at my local camera shop.

I had recently signed up for a class they offer that was going to cover the use of some new studio continuous lighting technology. The guy who was to teach the class was there as I was showing off my then newly acquired RB67 to one of the other guys. He looked at me and said (somewhat sharply) "You're not bringing that to the class, are you?"

Maybe I should have brought it, just to tweak him.