I asked myself the same thing. But if you look at it a different way, Bradley was the aggressor the entire time. Yes, Pacman was able to get cleaner and better shots off and showed moments of greatness, BUT for most of each round, Pacman was being the counter-puncher. Usually the aggressor will win if it goes the distance. But I do agree that Pacman was robbed in this bout.
Who knows, maybe Pacquiao "lost" on purpose so that the matchup between him and Mayweather will now be possible.