In the pursuit the Keynesian dream of complete government control over the private sector of the economy, many governments pay farmers not to grow food. Yes, they are paying them not to work. Can you imagine what would happen if they did this with construction workers? The theory behind this practice is that it helps the farmer by keeping the market from having too much food. Thus by paying farmers to not farm they insure that the prices do not fall to low for the farmers to make a profit. Anyone who understands how the free market works knows that this problem will correct its self if the government would leave it alone. Millions of farmers did just fine before the government became involved.
Growing up in a rural farming community gave me early exposure to the harm subsidies cause. I have a relative that used to have a dairy farm. To keep milk prices from falling to low the government began subsidizing local dairy farmers. He was paid more not to farm than he would have made if he continued farming. My home town used to have several dairy farms, but government subsidies have long left most of them abandoned and broken down.
Of course all of this dramatically reduces our food supply, thus increasing prices. While it is an inconvenience for you and me to spend more on food, it is disastrous in poor nations that depend on imports for food. Most people in developed nations spend a small portion of their income on food. In poor nations large portions of income are spent on food. When food prices dramatically rise, the people go hungry. These people have been backed into a corner and are lashing out in desperation. In times of desperation, dangerous things happen. Desperation led to the rise of communism in Russia and China; it also led to the rise of the Nazis. There are plenty of evil people waiting to capitalize on this desperation.