Kudos to Miley, but I wouldn't pay that much to look at any celeb. I am a movie fan and music fan to be sure and I have paid 50-60 bucks for a concert and all...but $250...to just go in the park and "maybe" see her and meet her briefly with 5000 others? No thanks.
I don't doubt that there will be a sell out crowd, 5000 in a snap. That doesn't mean it's priced well, just that some people have lots of $$$ to blow and/or are willing to blow lots on their personal obsessions/hobbies. I hope they have a good time. It's too bad that it means the park is going to be closed to the non-Miley elite.