Just because something cannot be explained, doesn't mean its cause is supernatural.Existence cannot be explained in total. "What came before the big bang?", for example. In fact, it is, I believe, the mainstream school of thought that the sole purpose of science is to produce useful models, not to answer the most exotic questions from philosophy and theology. So atheists cannot claim that denial of religious beliefs is a scientific position. All that we can say is that we have no scientific evidence supporting such beliefs.
90%, 99%, 99.999%...doesn't matter how many people believe something, that's not a good reason for me to believe it. As far as encounters with "others", most cultures indoctrinate their members from an early age that "others" exist, so I'm not at all surprised that people encounter them.So how can one simply deny a wealth of human history describing encounters with "others"? How does one reject out of hand what 90% of the world's population beleives to be true in one form or another? How does one ignore the tens of thousands of testimonials found in churches all over the country each Sunday?
I think it's hard for people with strong faith to imagine life with no faith, so they can only interpret atheism as religion. It isn't, though.All that is required is a simple leap of faith. Of course atheism is a religion.