That is what is cost us for the Pirate and Princess and I felt the same way when I bought the tickets. I couldn't believe I was spending that much money for tickets for a few hours in the park. When we actually went I was thrilled that we had done it.
The parties really are special, magical times. The fireworks are amazing - totally unique from what you see at normal closing. The parades are also good. The two best things that make this worthwhile for us though are the character expereinces and the rides.
The character expereinces are completely unique. My kids were able to see everyone that night and many of the characters were in costume - pirates of course
As for the rides - even though there were a lot of people the rides were all walk on. The kids got to go on everything they wanted several times in a row. This allowed for the rest of our vacation to be more relaxed and enjoyable because they felt like they really got to do everything they wanted to do at MK that night.
We are going to pay the price again when we go in a few weeks. It is expensive...but for our family it is worth every penny.