Well I can't really speak of the rest of NA, but where I'm from (Toronto), our selection of food, whether it be vegetables, seafood, etc. is vast. I have yet to see, any vegetable that I've seen here that I couldn't get back home. Well, some tropical fruits I guess, and even if we do have those, they're not great. As for veggies (used for stir fry's and what not), yah we have it. They may not be picked from the back that day, but nonetheless fresh as they usually come from some local farm.
Fresh fish? Of course. Wherever there is Chinese, the need/demand for live fish is there, you know we wouldn't have it any other way. I cant' go down to the pond and get me one, but I can walk into the many Chinese supermarkets, littered across the GTA, and have them bop one on the head for me.
I don't wanna nitpick, nor start a war of words, but most the uni sold in Japan is from California.