Kids: Trick-or-treat!
Ambrose Monk: Wait. Wait. Not yet. Trick-or-treat. I've accepted your terms, which means we now have an implied contract. By accepting this treat, you are in effect promising to refrain from committing any tricks against me or this property now or in the future. Are there any questions?
Boy: Yeah. Do you have any peanut chews?
Ambrose Monk: There's only what's in the bowl. Now, one per customer, all right?