Lots of scientists go to their graves defending pet theories in spite of lots of available evidence to the contrary.
This behavior has more to do with how much of the ego is invested in something than the ability to see or evaluate evidence as such.
"In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time someting like that happened in politics or religion."
But here is another quote to illustrate the counterpart:
"Die Wahrheit triumphiert nie, ihre Gegner sterben nur aus."
Rough translation: The truth never triumphs, its opponents simply die out.
That's by Max Planck.
There was a paper a while back focusing on abortion, which combined a bunch of statistics on who got them and what their political views were - the conclusion being that in the US, the Democratic party's ranks had been reduced as a result of their support for the policy.
The flip side for religious groups (who are generally anti-abortion) could easily be true.
Anyway, what with HN and humor it is probably good that this has been flagged off the homepage, but you may very well be right.
The religions we observe today are the result of - heavy irony here - an evolutionary struggle to survive, and simply because of that the religions that remain are pretty good at what they do, to spread and to remain. An atheist movement capable of competing with religion on sheer numbers alone would probably have to borrow bits and pieces from those very same religions in order to be successful in that competition.