Give a man a permit to eat a pig, and you feed him for a month. Give him a permit to sell wild pork and the woods will be empty. Give the government power to obtain revenue from hunting licenses and you’ll never get rid of feral hogs. Ethics has almost nothing to do with ecology. Life is just economics and humanity has figured out how to separate its economics from the economics of nature, so that our ‘civilized’ isolationism allows competitive extraction from outside city walls until there’s nothing left to hold up the walls.