Traditional agriculture has "solved all of the scale problems" through the use of pesticides, destructive monocultures, and disruption of the natural water cycle. It's also built on the idea that diesel is cheap both for the tractors to farm in the midwest and the trucks to deliver goods to markets around the country. Should any of those fragile pillars collapse due to regulation (not likely), major environmental catastrophe (pretty likely), or disruptions in the global fossil fuel economy (possible), solutions like vertical farming start making a lot more sense.