content: Think about how much insane stuff people are still doing to one another in the name of religion. One of the biggest religions today still has followers kill each other over a debate 1500 years old about who the 'true' successor to their prophet was. People take these books written by other humans and frame them as irrefutable and undeniable truth, even when we can prove various things they say wrong, because the persons who wrote them said god(s) talked to and through them. A more logical approach to existence could, at least ideally, help with so many of these issues. It gives people the hope of something beyond the unknown without all the complications of "Also, kill or convert everybody who doesn't agree with this specific mystic book. Oh yeah and don't have any fun - god REALLY hates it when you have fun." And perhaps more compellingly it doesn't rely on you picking the right magical story - it's simple raw logic and probability.