Sometimes a big hit is a penalty and fine and suspension...sometimes they are not.
It depends who you are and what team you are on or what team it is against.
Unless it is so obvious it has to be called. Then there is still a bias for or against certain teams and players.
Romo never got the calls, and now it seems Dak not getting them either. I am sure there are a few other QB's not getting them as well. But we know who always gets them when someone breaths on them.