... system to choose a champion is the fact that strength of schedule considerations often trump outright W-L records. Since most games are played in conference, each year's endless debates about relative conference strength are justifiably contentious. 

As passionate as those discussions are, opinions become especially inflamed over out of conference schedules. This is because in college football, teams have the freedom to select their own OOC opponents.

It is a particular sore point that many elite programs regularly choose to dodge quality opponents and instead play one or two "cupcake" games with 1-AA division teams. 
Bleacher Report - College Football