is going to be similar for a sold-out game regardless of whether the stadium seats 46,000 or 55,000. There's just a percentage of sold tickets that are not going to be used for a given game (and of course that percentage will change based on various factors). The bottom line is that no one is going to make a decision about expansion based on the fact that a certain number of sold tickets may not be used.

I would also note that for Utah games, the place with the most empty seats is the student section because it's GA and all of the students crowd down. The U can't issue additional tickets there even though there is space at the top.