I live near the University of Wisconsin. From what I can tell, the campus bike du jour is whatever's cheap and barely functional. Students bring their "nice" bike, and it gets trashed, or they get a klunker from Target. The attention attracted by fixies was and is greatly in disproportion to their actual use. But look closer. Most of those derailleur bikes are left in one gear, and probably have barely functioning derailleurs and brakes due to rust and neglect.