Strange as this might sound, I'm on Rich-Rod's side in this. I've seen some awfully terrible things said by fans of various teams: Ohio St, Michigan, Alabama, LSU, Oklahoma, etc. Rich-Rod's been mercilessly hammered this year, even though everybody has been saying from Day One that it'd take time to remold the Wolverines back into a contender. What he said to them could be applied any number of places, but frankly.... I can't blame him for it, although I don't have the text in front of me to quote in this thread.
I don't know the particulars of this story, but a head coach of a major college football team is going to have to have thick skin. That's part of why he's paid the big bucks. Calling the fans out isn't going to help, in fact it only makes him look worse.