Trick r Treat is only 2 hours in my town these days. When I was a young'n', I could stay out til atleast 10pm. My parents told me that when they were kids in the early 60's, they could Trick r Treat all of Halloween Week.
It's about 6 to 8 around here. Started trickling in at around 6:15. After 8 all you get are out-of-towners coming in by car, or Mexicans. Yeah, I don't know why, but Mexicans only come out after 8:00 PM. Strange.