If I grow up in a religious environment where I'm conditioned from birth to believe particular revealed truths (not in an aggressive, authoritarian way, but lovingly and persistently), and membership in my family and community is inextricably tied to those beliefs (not because of any looming threat but simply because it's an unavoidable part of their lives), and I am otherwise happy, I have great practical reasons to maintain my religion. Again, assuming it benefits me - not to say it does everyone in this situation - it's reasonable for me to want to retain those benefits.

As I am intellectually honest, I acknowledge that my belief is based in faith rather than proof. Since my core beliefs are thus inherently impossible to disprove, I have no reason to be persuaded by any evidentiary argument. In fact, the only possible relevant proof that could ever emerge would be proof that I am right, not wrong - anything that indicated otherwise would have to be a lie according to my faith.

With an actively beneficial faith and no possibility I'll ever be proven wrong, there is no reason for me not to assume that I am right.