Now we are on to the second major fallacy common around here, that not growing food in your backyard is some kind of environmental sin. Cities have been around for thousands of years, and they have always gotten their food from somewhere else. New York City used to be fed by New Jersey, Connecticut and the farms upstate accessible by the Hudson. This was not really any different than Alexandria being fed by farmers upstream on the Nile. Nothing particularly unsound about that. Indeed, given how long its been going on, I would say it's about the most "sustainable" pattern that anyone could ever hope to find.