The central way in which prejudice is shown to outsiders is through the experiences of the Joad family as they start their trip to find work and a livelihood away from their own land and roots. The experiences that they undergo and the challenges that they face clearly expose Steinbeck's feelings about human nature and the way that we are so quick to exploit rather than help those in need around us. Consider the following example from Chapter Twelve and the car salesman:
I ain't in business for my health. I'm here a-sellin' tires. I ain't givin' 'em away. I can't help what happens to you. I got to think what happens to me.
Again and again, we see that those who are in a position of power over those who are being forced to occupy a position of weakness because of their lack of resources is manifested through exploitation, greed, and selfishness. Here, the car salesman justifies his actions by his own selfishness and his need to look to his own interests at the end of the day. This represents a pattern that we see repeated throughout the novel as again and again characters exploit the Joad family because of their lack of power. This is one way in which prejudice towards outsiders is exhibited, as itinerant families such as the Joads find themselves opposed at every turn.