My kids are grown and out of the house now, so they're on the giving end of Trick or Treat now; but Trick or Treat in my area (my town and the surrounding towns) has remained a really nice tradition for kids since my kids were little (and before). With a few rotten things that made the news (and made Trick or Treating more of a safety concern than it had previously been), steps have been taken to make the event safer for kids. For example, hours have been set up two two hours, and people generally know to only bring their kids to the homes of neighbors they know (or at least neighbors who have been well known in the area by others for a long time). When I was a kid my older sister (at around 12/13) and her girlfriends would go all over the small city in which we lived,and then hit some neighborhoods in the next city over. These days (at least where I live), it's standard to see a parent or two (even a group) standing in the street (or in a car nearby) as a bunch of, say, 13-year-olds show up all together.
Parents of younger kids tend to go out in small groups, with the whole group of all their kids getting to Trick or Treat together. Sometimes a lone kid, or a couple of kids, will show up with just one parent. Either way, the parents are very present and very much a part of being there, watching their kids, and knowing which houses they go to. I try to make my walk and front door seem very welcoming and "happy" for the kids, and I try to make my Trick or Treat bags different enough that parents may remember who gave their child the treats in the bags (I assume they trust me after all these years). I just figure that someone who gives kids something bad isn't going to want to make sure parents will remember where the thing came from. (Besides, I live in a close, suburban, neighborhood where people pretty much know who else are also parents, even if their kids are grown or else too little to go Trick or Treating.)
Anyway, I think it's a nice thing for the kids, as long as everyone kind of works together as a neighborhood/community to keep Trick or Treating a safe thing. I don't think kids have to do what they used to do when my sister was going out. They can have a nice time without roaming through neighborhoods where nobody knows who lives where. (I get a lot of Trick or Treaters who are the city-dwelling relatives of my neighbors. I'm happy they have our neighborhood, where they can know who is who. :) )