Why does no one understand the brilliance that is salad mines? It's so obvious! See, when I am the evil overlord, we will be operating on a mandatory program of porn and salads for all. Obviously, we will need more salad stuff than can be easily grown above ground. So there will be tunnels lit with UV lamps. And inside, working hard to bring us our lettuce, will be all the people who do not whole-heartedly support the new regime. Also people I don't like. And salad doubters. See? Salad mines: providing salads for all while locking the undesirables away underground. It's a perfect plan!