The differences between country and city come through very clearly in Jay's encounter with the people on a covered wagon after crossing the river with his automobile. In 1916, automobiles were just coming into use, and demonstrated a drastic shift not only in transportation, but also in lifestyle, making the split between urban and rural more materially visible. Jay would never have had to get up at dawn to make it to the market on time; however, the people waiting for the ferry do. This country-city conflict represents a central concern in American culture at that time. Agee himself was born in Knoxville in 1909, when the town was rapidly becoming an urban center; his experience of the city's growth is evident in this autobiographical novel.
Agee's own family had ties to both the rural past and the urban future. He himself lost a father when he was young, and like Jay, his father came from a mountain family and embodied the characteristics of people who left farms and became urbanized. Agee's mother came from a different and much more urban background. Like Mary, Agee's mother was intelligent and passionately committed to the church. A notable difference between Agee's parents that is also present in Jay and Mary is that formal religion is very important for the mother, but not of much importance to the father. We therefore begin to understand that religious faith, like alcohol, is a point of contention between Mary and Jay that is likely to reappear in some form at a later point in the story.
The tension between urban and rural is felt not so much between Mary and Jay as individuals, but rather between the families of each spouse. We get the impression that Jay's family thinks that Mary looks down on them, presumably because she has had a more privileged upbringing, comes from a socially prominent family, and has been well educated. Likewise, we learn that Jay was probably raised in a rural environment from the fact that the more he drives into the country, the more it becomes "home country" to him.