The migrants are needed, and they are hated is the central idea.
Explanation:
The article is about the migrant workers. The migrants are considered as gypsies, foreigners and outlanders. The migrants had horrible living conditions without basic facilities.
The article distinguishes the dust bowl migrants to that of the imported foreign imported laborers. They were forced to work in inhumane conditions.
Later Steinbeck helped the migrants have access to clean facilities for hygiene and sanitation by organizing many government camps.