If everybody did that then we'd never get that rare treat of a game ...i.e. Michigan vs Appalachian St. in 2007. Some of those are good to confirm the hierarchy, expose pretenders....
Rent a wins are far too profitable to ever go away willingly. The FCS teams could easily charge double and everyone would still be saying "deal".
They really need to fix the SEC schedule so that players will play at least one game in every SEC stadium during their 4-year college career.