sectarianism in atheism

[FatAndFaithless]

Is atheism just as sectarian as some religions? There seems to be a few different camps out there from people who believe a more "pure" atheism, who do not believe in any "spirituality" to others who are "spiritual but not religious". 

Are there different sects within atheism and do some people believe their version of atheism to be "true" while another version of atheism is "false"? Is there an attitude or principle that would help avoid the formation of sectarianism?

I mean, there can't be sectarianism if there aren't sects.  There are different self-identified groups of people that happen to be atheists, but any difference in viewpoint on any given topic isn't a tenet or value of atheism.

There aren't any "versions" of atheism.  Atheism is simply the stance that "there is a god(s)" has not met its burden of proof.  You can be a socialist hippy granola muncher and not believe in god, and you can be an ultra-libertarian corporatist and not believe in god.  You can believe in ghosts and chakra and healing crystals and all sorts of "spiritual" stuff and still be an atheist.

Atheism doesn't drive values or beliefs because it doesn't have any content to serve as a foundation of a worldview.  Things like humanism, secularism, etc might, but "atheism" as a thing in itself does not. it's just a response to a claim.