I've seen at least 3 games where one person got an item multiple times, the latest being the first game of the just played lgd.int vs forlove game (match id: 88326566) where a user named "Roshan" got 4 consecutive item awards for multi-kills and the game end screen.

Hard to say how many users had pennants on due to the nature of them having fanfare levels and both teams in this case not having any pennants in store (I'm under the impression that it doesn't matter which pennant you have equipped in order to be eligible for an item drop), but it seems unlikely that a game with so many spectators and pennants can so often produce these kind of drops.