In their view, we'd be better off without it. Regardless of its appeal, it doesn't hold up under examination.
Religion is basic to human experience.
It is such a basic aspect of our experience that we can't get rid of it. Other creatures may live without religion, but people can't. We are religious to the core. Perhaps the main reason is our consciousness of the inevitability of death. No matter how we try to suppress it, we all know that we are living on borrowed time, making decisions that define us forever.