Disney is the quintessential American success story. Walt started with little, but built an empire that lasted way beyond his death. He became larger than life while he lived, and left a legacy that will likely last beyond the days of Captain Picard.
I love Disney movies, and I love riding Big Thunder Mountain, or Space Mountain, or even Captain Eo's Mountain (sorry...got carried away there), but it's not just the movies or the rides...it's the whole feeling.
For excitement, I could say that Six Flags Magic Mountain is better. They have much better rides (Superman made me squeal like a school girl the first time). For entertainment, well, there are a lot of movie studios that have kept me entertained. But Disney is more than that...it is an experience.
When I go to Disney, I leave the rest of the world behind. Going to Six Flags Magic Mountain I have to pass through a metal detector and then be pat down by a security guard. Even still, once inside I have to deal with a bunch of people that look like they are fresh out of prison. Interestingly enough, if you stay past 7 PM you notice the park gets much more pleasant...I guess parolees have to be home before dark...
ANYWAY...back to Disney. I can drive to Disney and park just outside, then walk to Downtown Disney (10 minutes from my free parking) and, almost from the place where I park, I am in a totally different mindset. It's like being transported into a different world! I don't have to buy anything, not even the caramel popcorn, whose sickly sweet smell permeates about 1/4 of the downtown Disney area. Merchandising aside, Disney makes sure that, from parking lot to parking lot, you are transported into another world: The Happiest Place on Earth.
I guess that is why I will spend $300 on an annual pass to Disney, but haven't spent $70 for an annual pass to Six Flags since 2005.