I think fans who ask this type of question, and there are several around here lately who do so, it's done to take the pressure off of themselves. They are so averse to experiencing a disappoint in the tournament this year, that they need a loss to give themselves just enough reason to doubt the teams abilities, so that expectations can be ratcheted down to about the same as a dozen or so other teams having good years. Then the eventual disappointment, so the psyche says, will be more tolerable.
If you've ever waited for a team that is almost unbeatable, a team you know can play with and most likely beat any other team in the country, well...here they are, right in front of you. This is the team you've been waiting for to give you reason to throw your chest out and challenge any other fan in the country to a throw down for greatest college hoops team in all the land. Enjoy, and stop questioning the success. They are damn good, and will continue to win, just might win it all. The only reason I could think of someone having such a losers mentality is for selfish reasons. Enjoy the ride. The team is confident they can keep it going, why shouldn't the fans be too?