Why, because for some reason its in Baseball's unwritten code, thou shall not break up a no hitter in the 9th w/ a bunt single. At least I believe that is section of the unwritten manual that Bob Brenely referenced a couple of years ago.
I agree that it is the batters primary job to get on base any way possible when you're down 2 in the 9th. If a bunt single gets the job done, then by all means, I personally don't have a problem w/ it. However, I do question if they will hit him next time the 2 squads face off. I've been told that his is what "scrappy" teams do