There is some truth to this, but I do not think it is just the Eastern zone. The Eastern and Central zones have a distinct advantage in terms of the number of potential viewers. It is not a bias towards the schools in the East as much as it is a bias towards the time of day the games are being played and the number of people who live in the Eastern + Central zones compared to the Mountain + Pacific zones. More people can watch games that are in the Eastern and Central time zones than can watch games in the Pacific time zone, and there is not much in the Mountain time zone. If you look at the potential number of viewers conference-by-conference, the conferences with most of their teams in the Eastern or Central time zones (SEC, Big 10, ACC, etc) are going to generate more total viewers nation wide than any conference in the Mountain or Pacific time zones will. Very few people in the East will watch a game that does not even start until 11:00 PM.
Now, if you are only looking at regional viewerships, then the PAC 12 should stand up well compared to any of the conferences in the Eastern or Central time zones, but DirecTV is a national provider. On a national basis, there is no PAC matchup that could come close to the number of viewers that a Michigan/Ohio State or a Alabama/Georgia game could generate. The highest nation-wide interest for PAC 12 games are for the non-conference matchups (Notre Dame/USC or Notre Dame/Stanford).
Totally agree. I actually made the same point a long time ago. It is not just the following but the game availability nationally in good time slots.