A lot of the food already pretty much is. Modern production tractors and implements have the technology to operate without much human intervention; only really relying on an operator to monitor that all is well with the system. We have robots to milk cows, collect eggs, you name it.

The technology improves each year, but robots are nothing new to agriculture. Farmers started experimenting with this technology as far back as the 80s and it has only become more pervasive since.