Well, it is also the parents that have to worry about how they are going to do halloween, and if one still has kids of trick-or-treating age, how to explain/deal with the sadness.
Up were I live, only the newest/youngest neighnourhoods still go door-to-door.
Everyone else goes to either the community centers or into the malls (and go store to store).
In the last decade, my parental units had on average 5 people going to their door for trick-or-treats, while a person working in a mall said they have been average 600-700 trick-or-treaters. Last year it was 850!