Well, in fairness one can be concerned about the implications for the planet's health of collapsing fisheries, and also wonder by what moral authority we deprive another species that appears able to feel pain and joy of their home so we can have a diet with large amounts of concentrated vegetable oil.
I KNOW. But, difficult as it may be to believe, sustainability still isn't what I was talking about. And, no, that doesn't mean I believe it isn't a problem.