There are major parts of the world I don’t trust my fish to come from (hello, China), but I see no reason to avoid herring from off of Europe or certain farming techniques, such as how young oysters are fostered in the Long Island Sound.
I expect you save money buying non-American goods from the free market, and there’s no reason that people who work in other industries shouldn’t, on principle, be able to similarly turn the tables on you. Protectionism for me, but not for thee doesn’t seem particularly principled to me.
All that said, localism for food, where possible, does make a lot of sense.
I never considered oysters as farmed but now that you mention it they are.
At least here they are.