Non jw here, Halloween was great fun when I was a kid! Parents never went with you and naturally it was dark. The boys tended to go farther than us girls so they had quite a haul. We would go up into the 'rich' subdivision and some even gave out full size candy bars! exciting times I tell you.
One house had a note on the door about not celebrating, none of had ever heard of jw's and didn't know what they were. That poor kid got labeled as some kind of weirdo. Their house was dark, don't know if they were hiding out in the basement or something. I think their windows might have gotten soaped one year. That was the extent of shenanigans by anybody.
Longhairgal, yep, us too! got home and dumped everything out so mom could look through and toss anything questionable. (hint for those of you just beginning to participate- don't make homemade popcorn balls unless they are for people you personally know, they will be tossed. If you are old and think apples are a good treat, err, no, don't give apples either)
When my kids were young school had 'book character' day right before Halloween. It had to be from a book they had read. That way all the kids could participate even if they belonged to a nutty cult. Not sure if any jw kids did or didn't participate as it was really just a politically correct way to let the kids have some Halloween fun. Pre jw spouse days for me so they weren't on my radar yet.