Actually, I knew a guy that did the exact sort of thing Dodo is talking about, only he was cool. When I was in my early and mid teens I used to hang out at his hous a lot. (What can I say? He had three daughters, all within 2 years of my own age.)
Anyway, he always went in big for Halloween. He'd decorate the yard and the house, and usually set up a couple of contests for the kids to "win" their treats with. One year he dressed up a scarecrow and put it up by the drive as part of the yard decoration. He put in a lot of time making it look just right, too. Then on Halloween night, he dressed up as the scarecrow and took its place. A lot of kids got a chance to pee their pants that night. The kicker was great, too. He already wore a full beard halfway down his chest and long hair... up under the scarecrow mask he was made up to look like the wolfman. Much hilarity ensued when a kid would get coaxed to take off the mask so they could see it was "just Mr. Bobby."
Good times, those were.