While I can understand the frustration with the price increase, I don't necessarily fault Disney for acting in accordance with supply and demand. As someone who is planning to run the full next year (by then, it won't be my first, but as of yet I haven't completed a full), and having thoughts that the Goofy might be fun, I feel rather frustrated that the race fills up within weeks after registration opens, nearly 11 months out from the race.
If a price hike (and I do agree that is a bummer, since I may end up paying it, I really do) has the effect of making a few people think twice about whether or not they really want to do it, and gives some others a little more time to think about it before feeling like they have to register or miss their chance, then maybe that isn't the end of the world.
Or, look at it the other way, too. Imagine if the prices (for all three) were lower, and closer to what you'd expect from many other races, say $50 for a half, and $80 for a full. How many more people would sign up that much more casually, without even taking it seriously, maybe deciding not even to show up at all. And how much faster would the registration fill?