It is my experience that only the very insecure or very young will so categorically dismiss the Bible. Me, I don't believe most of what it says, but then that's my view and I don't actually *know*.
(And the same goes with just about any so-called holy book.)
Third category: the very very disillusioned. Recovering catholics such as myself tend to have pretty contentious feelings about their once-religion. I'll admit I'm biased but I also grew up with this shit and know a fair bit about it because of it, so I do think that lends some validity to me comments on it above and beyond mere nose-thumbing.
Ah, I am glad to see I'm not the only recovering catholic here!
Even my wife, who is a devout catholic gave her blessing to using condoms during our dating phase and me getting a vasectomy after Amber was born. She may be devout, but she is also wise! Glad I married her!