What disgusts me most is how the fins are harvested. The sharks are dragged up, the fins removed, then the still-living shark thrown back into the sea. If the industry used the whole shark, it wouldn't be so disgustingly wasteful.
I've actually tasted shark fin soup, and most of the taste comes from the chicken that's cooked with it, something confirmed by people who know more about it than I do. I suspect the popularity of shark fin lies in its relative rarity, its consumption a statement that one can consume something so pointless and expensive. A lower grade version of the rhino horns and other stuff there also seems to be a market for. Whose harvesting is also similar to that of shark fin, the horn hacked off and the rest of the rhino left to rot. But I guess ostentaiously wasteful decadence is a proud part of the Chinese culture, or at least the top end that some people aspire to.