Well, according to Wikipedia, the origin of the candy-giving may have originated from the Irish tradition of "guising." Here an article: http://en.wikipedia.org/wiki/Trick-or-treating
Lookie here, we're turning into a research bureau. Soon enough, we'll have a degree in Halloween Economics and History.
Sorry, just the fact that most of you don't care about Halloween, yet are going to Wiki for info, amused me.
Anyways, nice to see you all.