or the star player that everyone knew to a life of relative anonymity where they are basically like everyone else is very difficult. If you play D-1 college football, odds are you have been the star for a significant portion of your life. So to then get to a place where you are working like everyone else and trying to support your family just like everyone else can be a big hit to your ego. I get the sense that some of them never adjust to that.
Twitter provides a venue where they can voice their opinions and still feel like they are relevant.