If you can buy a season of episodes on DVD for about $40 and there are 24 episodes in a season that is close to $2 per episode. There is packaging and profit from the store so NBC does seem to be unreasonable in this case. Regardless there is content coming from everywhere and networks have a lot of competition, so even so a few will miss the content there will be so much content you wouldn't hardly know a few shows are available, rather then visiting hulu.com people will just buy some other show to watch.
For now, the users lose. Right now, iTunes is probably the best way to get TV shows online and legally (although ABC's free video player is pretty excellent), but it's hard to imagine that the $2 per show model will still be the dominant one a few years from now. It gets pricey quickly.
