That's one reason that I find it puzzling that people could actually believe that Christianity is meaningless without creationist beliefs.
From my first hand experiences, it's as if people are proud of sacrificing Reason in order to uphold their faith. Their faith is so powerful, supposedly, that it overcomes Reason. I get the distinct impression that this is supposed to impress people. It never impressed me, and in fact led me to question my own faith at a young age. I lived in the middle ground for a while, knowing that my christian beliefs did not hinge on the literal accuracy of Genesis. When I moved towards atheism it was not because of YEC, but it certainly shaped my view of faith in general.