Come on people fans boo. When the coaches elect to punt on 4th and they send out the punter and the fans boo are they booing the punter? Of course not!
In this case fans were booing the coach for taking out the "hot hand." Everyone remembers the night when Prince hit threes on back to back to back to back to back possesions agaisnt UNC. If Tubby would have called timeout to replace Prince in the middle of that streak and brought in someone else would the fans be booing the new guy, no, they would be booing the decision to take out Prince.
You just don't take out a guy who has the hot hand, is in the zone, is feeling it, is unconcious, etc.