Well, I know enough spiritual people that believe their rationality is a gift that should be used. I guess how people define their reason and what constraints they put on it can make a lot of difference, though.
I mean, you get someone like Soren Kierkegaard who used reason to show how there is nothing that can be perfectly known in this world and thus spawned the notion of Christian Existentialism, to someone like Josh MacDowell and others practicing conservative apologetics who use reason but a reason that is always bounded (and thus defined) by their spiritual beliefs.
Both would even say "faith is the primary decision" here, but both came up with very different answers to what that means.
(And you even get the popular atheists of our day who claim to have yet another handle on reason.)
By the time you're dealing an adult religious person, they've already tagged all of their life experience under the perspective of their religious faith, and it's very very hard to get them to recast anything because it means basically deconstructing one's entire past and identity and rebuilding. So it's not just about deity being convenient or pleasurable to believe in, but also because to change a lifetime of believing in the divine means momentarily at least entering this space where nothing has form, nothing makes sense, and you no longer know who you are or what is true. Not everyone can survive that process, at least not alone.