No one seems to get this, so let me explain.
TV stations pay for rights to broadcast. ESPN/ABC has a contract with xgames, NBC has a contract with dew tour and grand prix. ESPN chooses to steam online live but nbc doesnt. They want people to watch the broadcast on tv so they can make more money off of advertisers. Sure, alot of people would watch it online but that market of advertisement for big tv stations like abc/nbc/cbs hasn't progressed quite yet. NBC will restrict the live streams in their contracts so that they can get more viewers on their tv broadcast. maybe < 100 people might get mad, but those companies don't care. even if those 100 don't watch, 10s of thousands, maybe 100s of thousands will still watch it on tv (a small fraction of that, maybe 1% actually being people who are skiers). Its just how it works.