It's weird, really. Halloween was definitely a thing when I was a kid. A long time ago now. You would make Halloween-y things at schools and pumpkins would ham-fistedly be made into lanterns. There would be ghost stories and such. We didn't trick or treat, though. I have this vague recollection of maybe being slightly jealous of our American cousins and their candy harvesting antics while adults were disapproving of the whole thing. Halloween wasn't really a big deal, though.
Somehow, it's all changed. Trick or treating has been imported wholesale and our exploitative capitalist scumbags beloved retailers have fully embraced the opportunity to sell vast quantities of tat on a massive scale. It's become a big deal in the same way that Christmas and Valentines Day became a big deal in the past. Whatever meaning these things once had has been lost in the revenue maelstrom. It's not something I can ever embrace. I'd prefer to have the old pagan festivals back myself.