Sorry for the late reply. Atheism doesn't imply hedonism. I define hedonism as flesh based pleasure pursuits involving things related to sex. The connection to atheism is more of a stretch but basically, Christianity has a puritanical stance on sex. Sex is related to morality by religion. So with the absence of a religion, I think that frees up our internal values so that people can pursue whatever they want (not including criminal sexual acts).
So, atheists have potentially more to bring to the lust table because they can approach it without guilt and with safety. In my experience, most atheists I know actually live quite vanilla lives. It's the Pagans among my friends who tend to get the most innovative. I think atheists have the ability to outperform even them because I think pagan beliefs are as nutty as faith in Norse Gods. But my experience hasn't followed my suspicions yet with most of my polyamorous peers, gay peers, lesbian peers, and orgy/swinger types having some level of faith. I think that's odd.