Some people need to drink less Butter Beer
http://movies.yahoo.com/feature/movie-talk-harry-potter-fans-deemed-too-heavy-for-wizarding-world-ride.html
People are mad about this but its your own fault if you can;t fit in it.
It might be worth noting that in some states, like Ohio, they've repeatedly tightened safety regulations for amusement rides. In particular the way shoulder belts fasten. End result is fewer people fit in, especially taller people with large builds. For example, here in Missouri, my one friend is 6'4" and heavy, and my other friend is 6' and weighs the same as my 6'4" friend. Guess which one can ride almost any ride, and which one can't ride a great deal of them? My 6' friend can fit them all, despite looking like he should have significantly more trouble. In particular, if a lot of your height is in your legs, you'll often have issues.
But yeah, this is nothing new. Just thought I'd relate the experience I had with it.