Yah, if someone's in the line of a jump and are not actually hitting the jump. They are a major risk, and pain in the ass.
You're never supposed to be at the bottom of a jump like that, unless you're hurt. But you're still supposed to get out of the way. Unless you're like seriously hurt.
Im all for having fun, showing your tits and getting fucked up on a river float but it can be done without being a pig.