Halloween

I don't get it, I really don't. You spend your years as a parent, telling your children to never ever take sweets from strangers. Yet, one day a year, parents all over the world, dress their kids up in fancy dress and encourage them to knock on strangers doors and ask for sweeties. Why do we do that?
And I feel guilt because I haven't done the trick and treating with my son... guilt - seriously!!!!! I've let him go around our street - and the people he knows, but strangers? Nope.
And I don't think I'm a bad parent for this. So there!