I remembered one of the most shocking moments I learned in my College days was that fugu could be eaten. If it did shock me to learn that cassava can turn poisonous and deadly then it also shocked me to learn that blowfish (called fugu in Japan) can be eaten if it's prepared properly.
What I could remember is the preparing the blowfish is no walk in the park. If you puncture the liver or any of the internal organs then that blowfish can't be eaten anymore. The risk is that blowfish contains a lot more poison called tetradoxin in the internal organs. Throwing away the toxic waste requires special waste management because the poison is more potent than cyanide. Preparation isn't easy so it justifies why the price is so expensive.
Speaking of which, I remembered that episode in Dragon Ball where a young Goku got punished for slacking off - then I thought Master Roshi and Krillin were going to get poisoned from eating blowfish. But years later, the real problem isn't the blowfish but how poorly prepared the blowfish is. But if it were farm-prepared blowfish (which doesn't eat the algae at sea that makes it poisonous) then I guess that explained why Master Roshi and Krillin didn't get poisoned.