Guys, it's the NFL. They would do whatever they can to win, and it's not a question of is it wrong because others are not doing it or even side affects for health. The ONLY reason these coaches, athletes and staff have any concern is whether or not they get caught.
If guys are playing football since middle school, eating like horses all through college and taking protein gainers and creatine while lifting and practicing all along the way, why do you think they still have reason to explode in the NFL?
It'd be like having 12 x 1500 meter runners graduate college every year as 3:38-3:42 types only to all get down in the 3:32-3:34 range their first year out. If that happened year after year you'd start to think their was some kind up "supplement" system in place in the big leagues. Or eventually you'd just get used to it....ehh-hem...the NFL.