I am an enthusiastic supporter of Halloween trick-or-treating, but that has been very much a volte-face for me since emigrating to Canada a dozen years ago. Long-time Canadian families grew up with this neighbourhood tradition, and so understand (and encourage their kids to comply with) the unwritten rules and conventions. Which, when it boils down, amount to "if you don't see a lit jack-o-lantern on the front step, they're not playing, so don't disturb them." It seems that most of the problems of yobbery in the UK stem from the fact that the tradition (with notable exceptions in teh parts of Scotland where "guising" has gone on for centuries) is relatively new and little understood.
Elementary schools encourage their pupils to dress in costume for today - with the proviso that they can't wear a mask that obscures their face. And they have to be able to sit down at their desks, so the little ones with their cardboard-box robots sometimes struggle (which is ridiculously funny to watch, but that's beside the point...). At my kids' junior school, they also do a "halloween dance-a-thon" in the gym in place of afternoon classes, which raises funds for local charitable causes.
Lots of people go overboard decorating their houses. Animatronic ghouls; styrofoam graveyards with zombie arms sticking up (we have one of those, it's revolting!); bats and spiders hanging from the trees... Even very young kids, accompanied by parents, come round knocking on doors for trick-or-treat candy. Apart from anything else, it's a good opportunity to say hi to neighbours and catch up on local gossip

Except that this year, we're anticipating lower-than-usual foot traffic. The weather forecast for tonight is for torrential rain and howling gales, so some of the less-dedicated candy hunters will probably stay away. All the more for the rest of them - I don't want bucketloads of chocolate bars left over at the end of the night, because I'll only end up eating them, and that won't help my quest to regain the svelte figure that's somewhere in there under all the blubber...