Joe, Barry Bonds was a hall of famer with or without steroids. Difference being you take a guy that hits 500 home runs and turn him into a guy that hits damn near 800. GNC doesn't do that, IMO.
It also boils down the rules. If the rules say you can take x, y, and z at gnc, then it is ok. If the rules say no to hgh, then it is not ok.