You've tricked. You've treated. Now, what to do with all that Halloween Candy?! We have a long tradition of trading in Halloween candy which helps control how much candy the kids eat over the next few weeks. Halloween night, after I have checked through the loot (for razors, opened packages, "God Loves You" pamphlets*) we let the kids eat two of whatever they like. The next day...we start the trading.
Make Piles For Sharing. My kids love to sort their Halloween loot into organized piles. Smarties with Smarties. Chips with Chips. They voluntarily make piles for sharing with others. For example, Grandma LOVES Reese's Pieces so any and all Reese's go directly to the "Grandma pile." Then, there is candy the kids just don't like (for example, anything with nuts—they just don't like nuts). So there is a "Don't Like" pile (which either goes to the office or the garbage).
Trade Up. Offer your kids a trade up for their Halloween candy. "Trade in 1/4 of your candy for a movie afternoon." (You could also offer hosting a play date with a friend, date day with a parent, extra toy time). This gives them control over what candy they choose to trade and gives you control over how much candy is out in the open. You don't have to throw it all out—just put it away—and distribute slowly over the next few months.
Trade With A Sibling. My oldest daughter dislikes chocolate (crazy huh?!) but loves chips and popcorn. My youngest daughter is the opposite (they complement each other that way). So they are open to sister-to-sister trades to get what they prefer. Works for them and for us parents.
*And yes, the kids did get "God Loves You" pamphlets last Halloween. I guess someone was eager for All Soul's Day.