As a parent of very small kids, I think they're wonderful. You spend time with your neighbors, see the other kids, wander around together in costume, etc. It's great fun. Pass around candy and spend time as a community. Here's the thing: halloween is for little kids. If you're so mature that running wild through the neighborhood is the only way you get anything out of halloween . . . you're too old, imho. Go get a job. Focus on your studies. Grow up.
But that's just me. I was still a preteen when my family and community expected me to quit dressing up and begging for candy. I moved on to more constructive things. So that's how I think life should be lived. Maybe I'm wrong. Maybe trunk or treats mark the downfall of western civilization as we know it. But if you're looking for constructive, character-building experiences, maybe you should look elsewhere and leave candy and costumes, fun and games to the little ones. Maybe.