This one wasn't stupid, but I'm too lazy to start a Funny Questions People Ask You thread.
Security guy at the front desk as I walked in wearing my two-piece RoadCrafter: "That thing bullet-proof?"
Me, with a chuckle: "Just about."
You learn something new every day if you're not careful.
If you think I won't understand it just because you have to explain it to me, maybe it was bullshit to begin with.