Maybe you should do a little research on the creative ways teams count their attendance. Many teams, like the commuter school on the hill, count ticket sales - including tickets that were given away and season ticket holders that are not at the game - as paid attendance. So they will always have an inflated number for attendance. Some schools - like BYU - count actual tickets scanned at the gate for their attendance numbers - the the number actually reflects how many people were at the game.
I remember one game at the Rice Bowl about 15 years ago. Utah was playing Oregon and the announced attendance was close to a sell out. Skeptical people actually counted and there were something like 5000 people at the game. You can probably still find news articles about it.
In any event - the BIG 12 does not count attendance at the game - TCU does, and they can count however they want. I'm sure there were 41,000 tickets sold or given away. There certainly weren't 41,000 people at the game, and probably not even 10,000.