>>519608271
As far as I'm concerned this is the "Trick" to the owner for not opening the door to the trick or treater.

It's origins are in a pagan festival wherein people dress up as evil spirits and visit houses threatening to cause mischief, to which the homeowner must give them gifts to ward them off.
The modern format of this is trick or treating, a kid dressed in a spooky costume knocks on a door, makes the demand "trick or treat!" and if you don't give them candy, they throw eggs on your house. That's the game, that's the festival.

They didn't answer the door, they leave the gifts out free to take, it's on them for being both foolish and furthermore, unfestive.