I understand tiered pricing in races, but if a race "sells out" during the lowest price tier, and people get shut out of it even though they were ready to buy, that's not a price increase to incentivize, it's just a random price increase. These people would have readily signed up when the price was lower. Holding back, for whatever reason, no matter how justified, and then charging more to those same people who would have bought earlier seems wrong. Maybe I'm alone on this, but to me this is not the normal "incentivizing" set of circumstances.
Edited to add that this would be more like a local race saying, "sign up before the price goes up!" Then you go to sign up and they don't let you, then they raise the price and then they let you. You would shake your head at that right?