Why are the fruits and crops destroyed?

Spring is beautiful in California, for the cultivation of the trees in the orchards is the responsibility of men of understanding, who experiment with the seeds and crops to make them resistant to insects and disease. Yet the fruits become rotten and soft. The rotten grapes are still used for wine, even if contaminated with mildew and formic acid. The rationale is that such wine is good enough to be a drink for the poor. The decay of the fruit spreads over the state. It becomes evident that the men who have created the new fruits cannot create a system whereby the fruits may be eaten. As Steinbeck's narrator argues, there is a crime here that goes beyond denunciation, a sorrow that weeping cannot symbolize. Children must die from pellagra because the orange business cannot be made less profitable.