I won't answer the door on halloween any more. I used to get a big bowl of sweets for the kids with lollies, chews & stuff, but year before last, I opened the door and there were three 14 year olds standing there. They grabbed at the bowl of sweets and took them all. I know it probably sounds a bit pathetic, but it really frightened me because I just wasn't expecting it and it was quite brutal, especially as before they turned up, I must have had at least half a dozen sets of kids round, all polite and happy and I was enjoying the evening.
Since then, I don't answer the door on halloween. I draw the curtains, tape up the letter box (just in case!) and ignore the knocks.