OOPS, just jumped in... hopefully not too late and not to start a new line of parallel discussion...
First, I think the thing with the spear, and the first post by someone being glad it was illegal, has something to do with going underwater and some speargunner mistaking you for a fish, especially in poor vis environments (this is always a threat where I dive, since there are spearhunters diving at the same spots we go scubadiving and vis is usually under 10 feet). Next, in my country there are places - and a lot of them, actually - where the real issue is TO HAVE SOMETHING TO EAT. So, in that situation, I think the veggie x meat eater thing is kind of out of the main point.
On the other hand, and sticking to the original question, it is kind of weird to see all those beautiful living creatures underwater and having them as a snack while in SI... I'm not a vegetarian, but I don't believe I would eat any of it, not at that time, at least...