With the exception of Cro, all of the folks I listed engaged in criminal behavior. My point is owner and fans don't care all that much about players behavior off the field only what they can do on the field.
So while porn is considered taboo, it would be forgiven by the fans and thus the owner and coach if the player helped the team win.
Hypothetically: Spikes goes to the pro-bowl this year. After the pro-bowl he head to hollywood and stars in variety of the most disgusting hard core porn flicks imaginable. Is he going to get cut? I doubt it. If he did would another team sign him? Absolutely.
His stock rises and falls based on what he does on the field. Very few fans care what he does off the field, and if dozen STH canceled their ticket to protest the employment of a porn start, the team would have no trouble selling those tickets to others.