Yeah mono crops just sap the nutrients up and don't put much of anything back. I am all for urban food forests a la permaculture guild style, growing all over the place, on every sidewalk, everywhere! Imagine a world where you can just go outside and most of the food grows itself? I am still for importing. Otherwise, the real issue is maybe we shouldn't be living in cold climates to necessitate the import of nutritious food in the winter... not too bright for us to live in cold areas.