Fans are more sophisticated now than they were 30 years ago. Not to knock fans back then, but BYU was the only show in town, and people did not care if they were punking the UNMs, CSUs and Wyomings of the CFB world. Now they do. Fans want top shelf competition, and they want it at LES, not just on the road.
BYU will sell the place out in the years that home schedule is worth it.