I wonder how much of this has to do with Santa Claus, the Easter Bunny, and the Tooth Fairy. These are harmless beliefs given to children by parents who want to introduce mystery and wonder into their children's lives. Unfortunately, this can have a detrimental effect on children. Being told that these characters do not exist can be devastating, almost as though a relative or friend has died. Worse, most children learn about these character's non-existence from someone who does not have their best interests at heart; the believers challenge the unbelievers only to later have the truth, and their worst fears, confirmed later. This brings in the questioning of all of their beliefs and a distrust of the people they should be able to believe.
I hate it when people treat my belief in God and in my Church as though I was just another child believing in the Easter Bunny. It's a convenient myth, they say, a way for us to deal with events that are out of our control, to deal with a loved one's death. I don't have a good response for that. To me, every atom is proof of God's existence, but that idea has to be taken on faith. I fear that, because we have damaged so many children's beliefs in one thing, we have torn apart their faith in that which is real.