In races the power ups are sometimes banned, but not all races. This causes some riders to get annoyed as some play the game of trying to get the aero power up and take it into races. This power gives a huge advantage apparently during the final sprint and can be the difference between winning and losing a race.
I saw this in a KISS race - 4 lap on Watopia Hilly. I was in a lead group of C ride coming up to the end of the 3rd lap when we were caught up by the A group just as they were finishing their final lap - so I was in a prime position to witness their sprint.
I'm guessing I saw 12 guys with their aero helmets on.