Lets ban cops since a small minority of them also commit crimes. See how stupid that sounds?
When I see the NFL publicly fire players, and coaches and whomever else, who are involved in serious criminal activities, I will take your point seriously.
As far as I can see, and I can give a list of players a mile long who are still playing, despite being involved in violence and crime off the field, the NFL seems more willing to cover up their misdeeds rather than do the right thing.