How did the used car salesman take advantage of the farmers?

This chapter (Chapter 7) critiques yet another part of the business system. The owners of the car dealerships mean solely to exploit impoverished buyers. They do not profit from selling cars that will last, but rather from finding the most ill-used vehicle, giving it the appearance of reliability, and pawning it off on desperate farmers wishing to get to California. There is no compassion in the car sales, but rather a perpetual cycle of exploitation. This indicates what the Joad family must certainly have experienced to get their car to go west, yet places it in a larger context. The chapter makes it clear that they are not the only family to experience this.