It's the rafters who TRY to run over kayakers and laugh about it that really aggravate us . . . some raft guides seem to encourage rafters to 'whack the yak', with paddles if possible. Upstream paddler has the right of way of course, but there is the matter of warning and courtesy (if you're standing on end in a hole you can't always instantly get out of the way of a careening raft).
Wow! I had no idea that this kind of stuff happens. I guess the manners of the past no longer exist anywhere. I can't even exit a store without automatically looking behind me to make sure I'm not letting the door close in someone's face. To think rafters are actually encouraged to make problems for others is pretty depressing.