CiG
Approximately Infinite Universe
Historically speaking, religion has divided and ostracized people for no real reason.
This is an atheistic claim very few religious people would agree with though, the "no real reason" bit. I doubt different groups of religious people would agree with your implication that there's no real difference between the different religions.
This is exactly the kind of thing I'm talking about when I say atheism does have some beliefs contained within it that aren't simply the product of another ideology atheism is piggy-backing on.
If religion is a net negative for humanity and historical division is just one piece of evidence proving this, surely most people would agree with it no? Same with wars, violence and anything else the average atheist places at the feet of the religious as proof that religion is a net negative. The fact that most religious people not only disagree but would turn around and say "actually religion has done more good than harm for humanity" demonstrates that atheists make these arguments through a lens of belief that most other non-atheistic groups of people don't share.