I think the difference here is in fundamental belief. Atheists think that there is no such thing as hell and see that telling a child of this is child abuse and perhaps for you it is because you don't believe there is a hell.
For believers it is a very real thing, the afterlife (heaven and hell) so telling our children this truth is very natural to us. Preparation for death is a part of life for me and I will be teaching my children this and they in turn will discover this for themselves.
And yes - children do not go to hell. so I will never need to tell my children this.
And speaking of the Q & A audience. They were actually quite balanced if u note the applause for points made by each speaker. The laughs were for Dawkin's really dumb ramblings like his explanation of nothingness which is why he got ****ed off... Pell spoke way more intelligently imo.. But yes, I'm Biased!