I guess this is popular because of the 'oh-so-stupid-government' vibes. Yet (almost) everybody buys the cheap meat (which the non-alfalfa farmer is also selling in reality) subsidized by not growing alfalfa. And when the subsidiaries eventually are withdrawn and the local farmer cannot compete with some other guy at the other end of the world who externalizes cost, then everybody buys from the other end of the world and complains that the local economy is going down. There would be more to this story, but currently it ends with (almost) everyone buying cheap meat and complaining about taxes.

edit: maybe my story is the same as the alfalfa one