I don't think that any of the rides allow flash photography. They spent a bunch of money and time making the lighting right so that the people would enjoy the ride and get the experience, I flash will show things that aren't supposed to be seen to people that don't want to see those things that will be iluminated.
Think the Hunted House, the darkeness is there for a purpose. And your flash will effect the riders on either side of you for many cars.
Also, almost no live performace allows flash, most of the people using them it doesn't do any good as they are too far away for it to help anyway. Think of a football game, thousands of flashes going off, but no flash is going to help a couple of hundred feet from the action. And if you are close enough for it to help the picture, you take a chance of temporarly blinding the performer, and that can be very dangerous, what if they fell off the stage because the counldn't see where they were going.
Then there are things like specto where the flash iluminates the background, which wasn't meant to be seen because it is designed to be viewed in the dark with the lights of the floats being an integrel part of the show. Or illuminations, where the flash will do you no good, but will distract the others around you.