I can't imagine anyone whose dream is FB staying in college one more minute than necessary. Better coaching in the League, more money, getting to the second contract faster, better competition...
Matt L is the bad example that keeps being trotted out. He staying an extra year, in part, because he was injured and not ready, and he didn't have an NFL arm. Hard to think of any other examples of NFL-ready folks that stayed? There are more examples of guys that weren't ready but bailed for the League anyway.
I was an accounting major. If I had an offer from a big-time firm, I wouldn't have even thought about staying another year. That's like saying you want to stay in HS an extra year, as the Big Man on Campus.