"It's about time!" ?
I don't understood why people would expect pro sports leagues to be a substitute for the justice system. If these guys are criminals, then they shouldn't be playing in the NFL, because they should be in prison. Otherwise, why should it be up to the NFL to make some kind of moral judgement about the behaviour and actions of their players that are unrelated to football?
If they were janitors, would they have been suspended from their jobs? The only vague justification I can think of would be the NFL claiming these guys hurt the image of the league and could be driving away advertisers.