When should the dealer muck folded hands at showdown?

[Mandor_TFL]

I agree that releasing your cards face down towards the dealer means you should not be allowed to win the pot. Reason being is that if you say " Call " or say " Raise " you are held to that action. Why should " Fold " not be held to a similar standard. Putting chips in front of your cards indicates a call, and your cannot take it back. Releasing your cards to the dealer face down should be handled the same way, same as saying " Fold ".