...about on par with most of the responses I get when I point out to people that they're smoking in a non-smoking area.
Standing in line at "It's a Small World" (I had the kids with me, honest!), I pointed out to the guy in front of us that you're not supposed to smoke in line. He started to get angry and replied "Where's it say that?!?". I pointed at the map/schedule he was holding and said "in there." He let out an "oh" and at least he wasn't angry after that.