I think its because its fun for people. But if you want to hear the "My Opinion" from me. I think its really because some people started giving away candy so it started passing down to people so then now, most people give out candy now! ;{)
A popped Halloween treat is usually popcorn. People used to at one time, give out homemade popcorn balls as treats on Halloween. This is rarely done anymore. Now people may give out individual snack size bags to trick or treaters.
Night
Most people who prank will prank all year long. However, some people who prank will only prank if they are not given treats at Halloween.
Candy Rockets
You can find a variety or recipes for halloween treats at http://familyfun.go.com/halloween/halloween-recipes/ or http://www.halloweentreats.com/. One of my favorites is the litter box cake!
200 years ago, they did not hand out treats for Halloween. Dressing up like a witch, monster, demon would have resulted in your being punished. Trick-or-trating is a fairly recent thing.
for this Halloween it is a Halloween background.
YES, the Spooky Sweets & Treats: Halloween Gift Basket is for kids.
Almondjoy
Treats :D
There are lots of treats that are big this season for halloween treat bags. Chocolate it a big favorite for treat bags as well as small halloween toys.
the phrase trick or treat has an American origin because on Halloween people often give candy (treats) or lay pranks on each other (trick).