I think the idea is to stop eating or cooking them live. I kind of disagree with this though, seafood like crabs and lobsters taste best when cooked live…
There'll probably also be some weirdos campaigning the idea of not harming humans unnecessarily, but that's probably too extreme.
Still seems barbarous to me but ...
Hey, I guess if I was going to be boiled alive, I'd rather be knocked unconscious first too.