Is it really worth killing an endangered species for a 5 minute meal? No. Should we make exceptions because it's their "culture"? Fuck no. That's like saying we should continue to let middle-eastern men rape their women "because it's their culture".
This isn't 6000BC. We don't need to be the hunter gatherer anymore. Animals can be farmed and killed humanely, even fish. If people want shark fun soup go ahead, make a farm and do it humanely, leave the wild the fuck alone.