Personally, I have no problems with atheists passing out literature to kids, just as I have no problems with Jews, Christians, Muslims, Mormons, and Jehovah's Witnesses passing out literature to kids.
Christians proselytize because it is a huge part of our faith. It looks like atheists proselytize because they are afraid of religious people pushing their agenda on them, yet many atheists such as Richard Dawkins and his followers say that Christians shouldn't proselytize.
While I am no member of an atheist organization, I can clearly see the need. If left to their own devices, religious people would push their agenda and beliefs on everyone much like they have tried to do for centuries. Non believers need to organize to protect themselves from those zealots who want to legislate their beliefs into laws.
why is it retarded and why are you so scared of atheists in the first place
If your religion is valid then it should be bulletproof from a few atheists passing out pamphlets
If atheism is valid, then it should be bulletproof from religious people trying to proselytize, and therefore atheists passing out pamphlets shouldn't be a necessity.