People who are religious are idiots and should be treated like second class citizens.
For a moment assuming that were true: "insanity is just another view of reality".
Who are you to claim your view of reality is any better than anyone else's? Because you have all the answers? Because I sure as hell don't. Even though I'm not religious, and a firm believer in the empirical / scientific method. There is still a lot about the universe we live in that we don't know. I'm just accepting that "as is" - there's gaping holes in our knowledge still, and that's okay. I don't need some divine being to fill those gaps.
But I've long ago stopped 'judging' people if they feel different. If they feel they want/need a different explanation for the world around them, power to them.
Where my tolerance ends (and ends real quick!), is when those with worldview X try to brainwash the rest of society that their worldview is the only, true, valid one. And try to impose/enforce that vision (and any or all rules that come with it) on others. It's exactly that behavior which has been, and continues to cause so much shit in this world. Regardless of "X".
My reason for being non-religious is a simple one: in general, I think the world as we can see it, feel it, measure it, derive (physics) laws from it, reason about it etc (aka the scientific method), is the simplest explanation for how our universe works. Even though it's far from complete. Bring in a divine being, and all you've got is a more complicated explanation for the same (see Occam's razor).
But that doesn't mean you can't hold a different view, or someone else's view is less valid simply because it doesn't line up with yours (remember that to some degree, religion and science are not mutually exclusive!). Just don't interfere with me having my view, I won't interfere with you having your view, and we're cool. Comprendre?