The tribes don't necessarily net because they make a lot of income nor do the Makahs try to kill Gray whales for the food. They do so to perpetuate their treaty rights given them in 1855. They don't want to stop for fear of losing the rights altogether. The tribal guides on the other hand, just like you white guides, fish because they earn their living doing so. The tribal guides have a vested interest in keeping the runs healthy just as you white guides do.