The league has made a business decision that players are role models for others in society who are their fans, and that the public image of violating Federal law and sometimes getting popped for it in highly visible arrests is not a good image for the league. It’s why they have conduct clauses in contracts and include alcohol abuse and spousal abuse as items of concern. Other organizations aren’t dealing with the same public and political(*) profile, so if a warehouse laborer comes to work after beating up his wife the employer can handle it internally because nobody cares. A running back beats his wife or kid and even though it was off the job and had no effect on performance the league will publicly discipline them. (*) keep in mind if you compare to other organizations you should compare to only those that enjoy exemption from Federal antitrust laws. So not affronting Federal authorities is a key factor in the public image equation.