Every big school has to play some cream puffs for financial reasons. Maybe the real reason CU is now playing more "Big Teams" is because they have become a cream puff for those teams.....
Just Kidding. Seriously, NU plays these teams because they are cash cows. 75k are going to show up in Lincoln whether they play Sisters of the Blind or Miami. At CU, you aren't going to fill the stands playing Scrub U. When NU plays these little schools, they can keep more of the money than if they were playing a bigger school. It is about money for both schools. Money rules the day.
FYI La Tech beat up on everyone's favorite Fresno State last year.