I would stand behind my father when he opened the door to welcome the little masked goblins, and wait to see the looks on their faces as Dad commanded them to say, "trick or treat" if they hadn't already said it. He refused to give anybody candy until they said those magic Halloween words.
What my dad did from that point on, though, probably scared the little trick or treaters and frightened their parents as well, because what Dad did was grab their hoard of candy from them – bag, plastic pumpkin and all – and just before he slammed the door in their faces, yell, "TRICK!"
Of course he always opened the door immediately and returned their treats, but the looks on the faces of those innocent little children was priceless. Their bodies never moved. They looked like a photograph frozen in time – in exactly the same position as when Dad first closed the door. Their parents stood at the end of the sidewalk in shock – another still photograph framed by the doorway – and Dad and whoever was standing at the door with him would bend over in hysterics.
I am always tempted to follow my father's lead and grab the bag of candy from some poor unsuspecting child, but these days you never know what awaits you at the end of the sidewalk. And so I just say,