I suspect my parents, like most parents (including myself) followed an intuitive moral line in this regard. The kids were allowed to dress up and get candy, but usually in sweet, good-natured costumes (the "Hobo" being a frequent motif). When I was a kid, nothing would have given me more pleasure than dressing up as Batman, but that was just a step or two over the wrong side of the line. I was smart enough not to complain; I was still getting the candy, and I had friends who were denied that pleasure, too.
Cut to the present. My girls plan all year for Halloween. Thanks to their actress (and seamstress) mother, their costume whims are fully indulged. Three years ago, the elder daughter knew how to tug at the old man's heartstrings when she requested a Princess Leia costume.
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This year she's an all-too-convincing punk (no picture, sorry. Rest assured she'll come to your door). Her younger sister, meanwhile, is a mommy mummy:
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That costume is probably the trickiest one my wife has yet assembled. The picture was taken in our church basement, by the way: we held a big Halloween party, and lots of kids from the community attended. I thought it was a super idea, and quickly retrieved my old motorbike leathers and Greasy-Kid Stuff to make myself up like Squiggy.
Notice the ceiling. The tile was smoke damaged from the firebomb, so it's gone. The nursery has been gutted and thoroughly cleaned. The supporting timbers remain sound, and the nursery will be rebuilt. But I have to admit: even though the kid who was chiefly responsible for all this damage is in custody, I'm still more than a little nervous.
There is at least one house in the neighborhood that freely admits to doing voodoo-type activities on Halloween night. One doesn't have to believe in the existence of a paranormal occult world* to acknowledge that if a person is angry, or desperate, or just plain foolish enough to summon something Dark, they will be obliged. It may only be manifest in a person's character, but the daily news should convince anyone that that is phenomenon enough to do a great deal of harm to a great many people.
I'm not sure what else to add to that. It's a hokey thing to say, but I do believe we have to work at bringing what light we can to our particular corner of the world. Since the fires, I've pushed myself out of my own comfort zone by pointedly smiling and saying hello to every sullen youth who slouches across my path. I'm not sure that's enough to counter anyone's dark impulses, but it'll have to do until I identify the next discomfort-zone I need to breech.
*Although you should count me among the believers, I expect that most adolescents drawn to experiment with the occult wind up experiencing something similar to Bobby Hill in The Witches of East Arlen.