Embarrassed politically correct white people who would rather wipe the memory of these tribes out completely so they don't have to be reminded continually about our history of neglect and persecution. I have concluded that this is really what this issue comes down to. People who claim to be intellectual but cannot separate the issues or determine any sort of compromise to use it for future benefit of native peoples issues.
Having gone to UofI I find the whole thing embarassing and as a sports fan, I find the NCAA's selective enforcement to be even more hypocricy on top of the usual overdose.
The tribe in South Dakota that supplied the Chief's costume enthusiastically and wholeheartedly supported the tradition. The idea that all Native Americans were opposed to this was nonsense. The idea that it was the NCAA alone that forced this is nonsense.
The anti-Chief movment went on for years on the U of I campus, and killing off Chief Illiniwek is only the tip of a very large iceberg, where small but continually vocal minorities can badger public bodies into doing their bidding. My son attended UIUC (University of Illinois at Urbana-Champaign) and was a reporter for the Daily Illini (the school paper). He always told us that most campus demonstrations were a very small group of people that the media "cut to fit" so that they took up the entire frame in the camera, and everyone was allowed to assume that a very large crowd was doing the protesting. Not true. Another case of a tiny fringe group having the media as willing collaborators.