Trick or treating is when you go from car to car, or house to house at any month of the year and steal what ever you can. Since you're going to be going in their neighbours car there is no forced entry in trick or treating due to the sound factor (you can do it if you're quite). Unlike on halloween the best time is later at night when everyone's sleeping.
When a person is too old to go trick or treating, (usually at age 16) but can't resist the allure of free candy, they take a small child trick or treating so they themselves can go.
My parent told me I was too old to go trick or treating, so I used my friend's little sister as a scapegoat and went and Co-op trick or treating!
The time period after halloween when one goes to the store and buys a lot of the 50% off candy. Its adult trick or treating because you get more candy in less time but as with all adult things you must pay for it.
guy 1: Yo you going adult trick or treating later?
guy 2: hell yea!
guy 1: better get there before all the good shit is gone haha
Guy2 : yeah haha nobody wants to get stuck with the shitty almond joy pack.