having to pay for a park pass, and having to renew it every year.
If you can ski park fine even though that's usually obvious based on clothing choice and skiing ability.
Just having to watch a stupid movie and pay $10 doesn't keep anyone out of the park, if anything, it just encourages people who really shouldn't be there to try to hit jumps that're too big for them. A waiver should be the only thing necessary, signed when the lift pass is bought... oh and most of the best parks in the world have no park passes.
Oh but as for real things nothing. I love park I think it's the most fun form of skiing.