We have seen the pain and struggle that these people must go through in order to survive. These characters help contribute to the themes and symbols in the novel and with all the different traits these characters have, they bring more complexity to the story.
The migrants and the powers which force them to make their journey--nature and society--are frequently represented by animals. This is particularly the case in the relations between the Joad family. They all had such hard lives that no one had time to do what they wanted to do John Steinbeck uses his writing to illustrate the social and economic injustice that the common man faced during the The Great Depression.
The three main themes in the story are free will versus necessity, the holiness of every man, and the kinship of all man. These characters, throughout the book, develop different qualities and personalities. The majority of these characters' individuality lies within whom they symbolize.
They had a problem of labor shortage not unemployment that is why high salary was offered to those Okies who were employed to pack meat, cement clay, railroad and even ice manufacturers. The Great Depression in the 's, crippled the American economy, causing many to lose their jobs, homes, and land.
Jeffersonian Yeomen, historically, however, did not succeed in their goal.