Yes, I've heard variations on all these themes, too: "that it's full of troublemakers...that it was "sinister", that I should beware of teenagers who terrorize the elderly, that it was just begging, a bad American import, etc."
Actually, it's amazing what a visceral reaction my British friends will have when I bring up the holiday. And I have to agree, in my town, the day does seem to bring out one too many troublemakers, who seem to delight in the "trick" part of trick or treat. So, I'm with them there.
But. What irks me is that they will fight me tooth and nail about my nostalgia for the holiday itself. "You can't honestly like it. Why?" When I try to explain that it is a part of my tradition, in my particular culture, of fall and turning leaves and scarecrows and candy apples and ghost stories, I, more times than not, get either a quizzical, baffled look or one of total disbelief.
If say, my Bosniak friends living abroad (I lived in Bosnia for a couple of yrs) said they missed Kurban Bajram, a day of family, prayer, and feasting, I'd say, "Yes, well, fair enough." Of course, they'd miss something that was always such a part of their lives. (And I'm not saying Halloween is a sacred holiday

, just a holiday that some folk in some parts of the world "celebrate" as a part of their family tradition.)
And, after living abroad for so long, it is this time of year that makes me the most homesick. I miss
It's the Great Pumpkin, Charlie Brown, I miss bobbing for apples, I miss seeing the kids trick or treating. I'm nostalgic for all of my Halloween's past. I miss all of it because I associate it with the magic of childhood and the beauty of fall.
So, sure, when someone slags off Halloween or my nostalgia for it, I am defensive. I'm not pressing you to celebrate it (although the marketing geniuses at Hallmark may be), just respect my feelings for it.
Now, where's my bag of candy corn???