Chapter 15 is the most fully realized of the intercalary chapters, becoming somewhat of a microcosm of the book as a whole. With alternating intercalary paragraphs, the chapter shifts between the generalized and the specific, moving from broad descriptions of roadside diners and a wide variety of highway travelers to the specific story of Mae and Al. Recalling the symbolic position of the diner in Chapter 2 and Chapter 13, Mae and Al are both curiously connected and insulated from the world that is rapidly passing on the highway outside their door. Their business is their base, the solidity of which is protection from migratory hazard. At the same time, their survival is entirely dependent on the choice of travelers to stop at their restaurant. Their reputation among the traveling community is critical to their life.
The complicated system of support illustrated by this chapter is an example of the community unity expounded by Casy. Mae, like Tom, will go through something of a mini-education, as she realizes that individual survival is impossible. Acting toward one's fellow human with compassion and respect is necessary to survive. The incident with the man and the loaf of bread illustrates this concept. Mae is, at first, unwilling to sell a portion of the loaf to the migrant man. Shamed into a sale by Al, she seems to see the impoverished, yet proud, man and his children for the first time. Gruffly, but not unkindly, she sells nickel candy to the man two for a penny. Her act of compassion is rewarded by the truck drivers who witness it and leave her a large tip. By sharing with others one can accumulate strength, and in this case, rewards.
