The Grapes of Wrath encompasses the struggle between poor, migrant laborers—once tenant farmers—and “The Bank,” or rich land-owners. This struggle is an example of conflict between those who have plenty and those who have little. Steinbeck also weaves into the novel an underlying current of Agrarian philosophy: the land is considered an important part of human life and survival on many levels. Land is, under agrarianism, dealt with so that it may last for a long time, as the health of humans is dependent on the health of the land. The Grapes of Wrath looks at how the land has been destroyed by greedy over-farming, drought, and the Dust Bowl. Because of the destroyed land, the landowners, who are controlled by banks—dehumanized as “monsters” in the novel—are forced to kick the tenant farmers off the land in order to glean a larger profit to pay the banks. This pushes many families to migrate from Oklahoma, Kansas, and northern Texas to California, which is rumored to be a land of opportunity and promise.

The first clash between the poorer migrants and the wealthy landowners  is at the beginning of the novel. Landowners hide behind the banks they rely on to force the tenant families out. There is little understanding between the tenant farmers and landowners, and Steinbeck creates stark barriers, such as the nice cars the landowners drive and the ragged clothes the tenant farmers and their families wear. Characters like Jim Casy, Tom Joad, and Floyd Knowles actively fight against the wealthy landowners:

• Floyd and Casy fight at various points in the novel for the now migrant farmers and laborers to unionize for higher wages. Steinbeck shows the conflict through not only cruel exchanges of words but also through violence.
• Tom and Casy end up hurting the Deputy sheriff, and Casy eventually dies at the hands of men who are against unionizing.

Further barriers are created with labels; the landowners see the migrant laborers as “dirty Okies,” and if laborers are troublesome they are called “reds.” Much of the conflict Steinbeck creates has roots in American attitudes toward Communism. At one point, Tom even playfully claims, “Damn right, I’m Bolshevisky,” in response to being called a troublemaker. Although the names “red” and “Bolshevisky” have negative correlations, both Tom and Floyd seem to take pride in being “troublemakers” to the wealthy.

The biggest barrier that Steinbeck creates, however, is the relative mistreatment of the migrant laborers by the wealthy. Privileged store owners who have more means and money than the Joad family still overcharge, and landowners and contractors only see the migrant laborers and their families as a nuisance. Steinbeck's work suggests that the poor will help the poor, and the rich care little for the poor. As said by Ma, “If you're in trouble or hurt or need – go to poor people. They're the only ones that'll help – the only ones.” Ma's claim shows the general knowledge of difference: she understands that those who are similar to her and the Joads will help, whereas those who are different won’t understand and will likely clash with them. It follows that those who are struggling and in need are more willing and able to help and show generosity.

Steinbeck separates those who are rich—the banks and landowners—as monstrous or inhuman in their privilege. Portraying the financially sound upper-class in this way directs all sympathy toward the migrant laborers, who are depicted as the only truly human characters. Here, the largest difference is drawn: the migrant laborers are human in their loss and suffering, and the landowners and banks, who in their wealth and pride no longer feel loss or suffering through poverty, have become inhuman.