I read a really interesting book called How Minds Change: The Surprising Science of Belief, Opinion, and Persuasion, and the author made some very interesting points.

It takes a seismic change in perspectives to change closely-held beliefs that are intertwined with our identities. I grew up as a devout Christian in an extremely conservative protestent young-earth-creationist denomination. I spent my Sundays and Wednesdays listening to the values preached from the pulpit: love, humility, repentance, understanding, protecting the vulnerable, meekness, charity, and unconditional love.

However, these same people when outside of church would spew tirades about "the gays", how poor people are just lazy, and how prayer wasn't allowed in school anymore. The love that was exalted above all other values on Sunday was just a platitude to give cover to hateful grievance.

And that was almost thirty years ago; they've only gotten worse. That's why people are abandoning religion in droves. The values that they sell are not aligned with the actual values of their congregants. Like the old Jim Croce song, their philosophy is "Let him live in freedom - if he lives like me."

Furthermore, losing one's religion nowadays is not the social exile it once was. People have support structures outside of organized religion. It's one of the reasons that Evangelical churches are so against a social safety net: it keeps the excommunicated from crawling back.