When I've been asked at the farmers' market why organic food costs so much, I always have the same answer:
You can grow crops with labor, time and patience, or you can grow crops with cheap oil and chemicals.
We have some 50 million people out of work in the USA, and yet, the major ag equipment companies and universities are developing robots to pull weeds.
It's not that we can't grow the food people need without fossil fuels: it's that we can't grow the CHEAP food people want while they sit on their asses and play with plastic toys from China that they bought with the money they didn't have to spend on food, and the time they don't have to spend processing their own meals and preserves.
The wonders of technology and money have made people so unaware of their own response ability to the world that they believe they can't live without petroleum-based food: even though that type of food has only been around for less than 100 years.
We not only don't need the fossil-fuel foods: we don't need most of the people who have been selling the fossil fuel lifestyles, the fossil fuel investments, the fossil fuel transportation (most people don't need to go anywhere if the food is all being produced by less than 1% of the population).
Most of The Economy is for crap we don't need, jobs that shouldn't exist, wars over fossil fuel prices, and moving cars from point A to point B and back to point A: every....fucking.....day.