The problem with looting for food to get you through hard times is that there has to be someone who has food, who is not willing to sell you any, who you are willing to loot, and who won't just kick your ass as soon as possible. A realm at peace with its neighbors who loots a few hundred bushels from one of them during a drought is pretty likely to be torn apart by those neighbors. So looting for food is almost never an option. It makes powerful, long-term enemies.
