Children are so naive and trusting of adult authority.
i don't think i agree with that. i hear my son ask "why" all the time
we are wired to be curious and are also wired to have our curiosity quenched with a logical understanding that would fit within our capacity...
and hopefully our understanding progresses which would increase our capacity
for example; a child doesn't know the laws of gravity but would know there is something magical about a floating balloon...which is why i think balloons are fascinating to kids...then they ask why it's doing that and then they learn about empirical truths.
or, i'll equate the popularity of belief to the belief in santa clause for children...most american children believe in him and they talk about him and they share this common wonder about him. because their belief has been confirmed by other children, it makes it easier to believe in such a being, it's a truth confirmed objectively (like the floating magical balloon within the realm of their understanding)...until one of their peers questions it or lets the cat out of the bag