Well Peter, I have one in the same vein as yours; one I have remembered for years.
I'm traveling on the freeway one day and I spy a car with a bumper sticker that says Member Mensa Society. So I think, I gotta catch up to see what the really smart person looks like. I catch up, look over, and here's this guy smoking the hell out of a cigarette with all the windows up. As I let off the gas, all I can think of is, how smart do you have to be to consume something that will kill you.
My apologies to all you smokers out there.