The cars of the migrant people crawled out of the side roads onto the great cross-country highway, and they took the migrant way to the West. In the daylight they scuttled like bugs to the westward; and as the dark caught them, they clustered like bugs near to shelter and to water. And because they were lonely and perplexed, because they had all come from a place of sadness and worry and defeat, and because they were all going to a new mysterious place, they huddled together; they talked together; they shared their lives, their food, and the things they hoped for in the new country.
– John Steinbeck
The Grapes of Wrath, Chapter 17. When the migrant families are on the road west they discover that they have something in common, a shared struggle. So when darkness falls they join together to help one another, sharing food and hopes for a fresh beginning in the new country. In a simile they are likened to bugs as they scuttle westward by day and cluster near to shelter and water at night. This is an example of community and unity in action, where migrants working together have a lot more power than if they go it alone.