Right now, we only farm in places it's convenient. If food was worth anything at all, we'd all be growing it like we grow closet weed, house plants, landscaping, and pets, in every margin out there between our own back yards, every unused lot in town, and on golf courses, in parks, and ditches. I think people underestimate how much food can be grown on a small piece of land when intensively managed. I also think they underestimate how much food can be grown on land that is scoffed at by conventional growers.
The other thing to consider is how much work we're going through to burn as much burn as much production as possible to prop up high input commodity markets. We've been in chronically low oil prices for years.
We've got the luxury of criticizing what kind of fuels we burn to power our machines and heat our homes. The market forces of substitution and true supply and demand can do amazing things when allowed to. For example, we can grow mountains of corn to the point the price is almost always in a state of collapse, threatening to burst the farm inputs bubble.
Market forces would dictate one switch away from corn, but instead, there are a plethora of gimmicks out there to protect the supply and find new ways to use the corn, not to the benefit of the end user or the farmer, but the guys in the middle hustling inputs . The low price problem has forced a grow-or-go situation for many producers and now they're stuck with infrastructure that can't be repurposed, whether that's dryers, bins, barns, parlors, or feedlots.