One aspect of life in Gravesend that John illustrates for us is the difference between his background and Owen's background. Harriet Wheelwright, John's grandmother, pays particular attention to people's families in terms of who they are and where they come from. She can trace her roots back to the Mayflower, and her family was especially important in the founding of Gravesend. Owen's family, on the other hand, bounced around a lot and can't trace their roots back to anyone "important." Owen's family's class has a big effect on the opportunities available to him: he goes to Gravesend Academy on a scholarship and with Harriet's help. He enters the army because he can't pay for college otherwise. A Prayer for Owen Meany shows us really interesting things about how people's attitudes about society and class are shaped by who they are, where they come from, and what opportunities are available to them.
In A Prayer for Owen Meany, the subject of class comes up frequently so we can see how it is an arbitrary and insufficient way of assessing a person's true character.
In A Prayer for Owen Meany, most characters adhere pretty closely to the roles that society carves out for them.