While raising Kids 1, 2 and 3 my policy was as follows-
1. dress up
2. knock on doors, get free candy
3. eat whatever you can stomach while trick-or-treating
4. the following day after school eat until your sick
5. the end
Now that I am raising a little girl with a sensitive stomach I can see why lots of parents only allow their babies to eat a certain amount per day. Kid4 is in love with candy like I am and she WILL eat till she's sick, like REALLY sick.
In comes the Halloween fairy. This is a WIN WIN for all of us. Kid4 choses 10 pieces of candy and she leaves the rest out for the Halloween fairy. When she wakes up, the fairy has left her a toy that she really wanted in exchange for her candy.
Does she voluntarily do this?
Yes and no. She asks if she can keep her candy. She often says no thanks, she'd rather have the candy. I say no and in the morning she is THRILLED with her new toy. It works every time and we're both happy.
The moral of the story? I get her candy.