Not because she's unfair. Dr. Paul announced his candidacy on her show, you know. I'll let the video speak for itself:
Find the point of contention, then pursue it doggedly, from many angles, until you get an answer. She created this story, by being good at her job. David Gregory would have dropped it after a halfhearted followup. Of course, Dr. Paul could have stopped it from being a story by simply saying, "I believe the Federal Government has the authority to force integration of privately owned, publicly operating businesses and resources." Or something to that effect.
The problem is that he doesn't believe government has that authority, since he's a libertarian teapartier. Because if it has that authority, then he's given up the ideologically pure position and opened the door to all sorts of regulation.