Hey, bears aren't so bad (unless you're Colbert).

This is why agriculture has been subsidized since the beginning of the country.  The Midwest was much better suited to crop production than the East, but the markets are far.  This led to the whiskey rebellion (reducing the size of the corn crop to whiskey which is easier to transport).  The canals were built to allow Midwest farmers to market their grain, followed by the railroads.

Farmers have always been in the business of producing something of more value than the raw agricultural product (meat, cheese, processed food, etc.) or work off farm in addition to on farm.  A farmer in the Midwest can grow about 1000 acres of corn and soybeans in about 4 weeks time (2 weeks at planting and 2 weeks harvest).  That leaves the other 11 for off farm income.  The work is time sensitive.  There is a narrow window for planting and a narrow window for harvest which makes it impossible for one person to do the work year round.  Farming does NOT provide year round employment unless it involves livestock or is in a climate that is conducive to year round planting and harvesting.

Think of it this way.  If the rest of society is improving productivity (producing more per person), then for farmers to keep pace, they have to be more productive.  That means some combination of farming more land, producing higher yields, processing the food to add value or off farm employment.  Slacker farmers (producing less but getting much higher prices for their commodities) is not an option because food is traded globally.  Then there are subsidies because the whole system does not generate enough income.  

The other thing about food production is that society cannot afford to let it be run by supply and demand.  Supply and demand would produce scarcity and periods when many people would starve.  This is why we have subsidized over-production and food storage to make sure there is enough food in bad years.

Donahue gets the economics totally wrong.  Most food has a limited storage life.  When food is very plentiful there is more available than it is possible to store.  The price goes to zero and what cannot be marketed is discarded.  This has little to do with capitalism and a lot to do with variation in agricultural production which cannot be tightly controlled (like a widget factor) but has large ups and downs that are dependent on factors (like the weather) that are beyond human control.  In many cultures, excess food is fed to livestock and food stored "on the hoof" and consumed when other food becomes scarce.

When there are shortage like last summer when corn prices were double what they had been, farmers make money.  Of course this was accompanied by increased starvation in parts of the world.  So managing farm production on a "just enough" basis is bad for the rest of society.  This is why we subsidize overproduction and storage.

How much is stored against future bad times?  We note that parts of the world that go through periods of massive starvation (we have all seen the relief effort) have inadequate long term storage.  Either they are not growing the right type of crops that have a long enough storage life or they lack adequate facilities and means to store food.

In the US, we have a whole class of elevator operators that are in the food storage business.  Even they cannot store enough food locally to get past severe droughts or other adverse conditions, so the food shortage problem is solved by a transportation network.  In areas of the world where mass starvation occurs, it usually is accompanied by adverse conditions (environment, war) that limit crop production.  Because storage and transportation are both inadequate (and the people often have no other source of income) they starve.  The way to prevent starvation is to subsidize overproduction and storage during the good times so there will be enough food to carry into the bad times.

The family farmer is part of the National mythology of the US.  The "Family Farmer Myth" is no closer to the truth than other National Myths like The First Thanksgiving.