I think the problem you're seeing with atheists (and what most religious people seem to mirror, I find) is that they assume they're somehow UNHAPPY and that their lack of beliefs bring them nothing but quandary and arrogance... rather than a sense of peace. A lack of faith (or belief in science and "truth") can lend just as much piece of mind, comfort, community and so on as your affiliation/belief with church can... just in a different way.
The idea that the faithless MUST find faith to find peace is exactly what atheists find so offensive about religion.

(Disclaimer: I don't pretend to speak for all atheists).

As the rest of it: I have never listened to, nor know a thing about, ICP. And I have no idea what juggalos are.