Same thing happened when Warner was quarterbacking. He'd get slaughtered, hit late, hit hard, hit cheap, and nothing would be called. Otherwise, the scores would have been so lopsided...
I talked to an ex-basketball ref who told me that word was, throughout the officiating fraternity, that you didn't call traveling on Dr. J in the third quarter. He did it all the time, but you hafta show the fans what they wqnt to see...
Games would be slowed to molasses flow with incessant penalties, and drives being stopped by penalties for holding Donald or his success nailing quarterbacks or runners for a loss would result in booing fans, etc... The league can't have that. It's a dollar-driven entertainment enterprise.