Of course they don't, but it's also usually not that obvious, especially when the intended receiver (I guess I should say the guy who ends up catching the ball) is the one pushing the opponent in the back and to the ground right before the catch, and out of the pile a bit (which is what made it obvious). It didn't help that the referees had two other horrible games on Sunday (at least), and that they have been calling PI very questionably to begin with. I definitely don't agree with all of these players tweeting these things (maybe being pissed off, but not tweeting how the NFL is shit), and Clay posting Goodell's number, but taking everything into consideration, I can see why they'd be mad. I think my biggest problem was the fact that they went to replay, and still didn't get it right. That's huge.