The first thing to understand about Faulkner's work is that he was not writing about "society" in As I Lay Dying. He was writing about a rural sector of Southern society. There is no expectation that significant parallels might be drawn to a universal society. Faulkner's aim is to exemplify select segments of Southern society. It is true that there is the expectation that universal truths about human nature might be drawn from Southern narratives, but this expectation does not necessarily extend to the universalization of Southern society as revealed by Faulkner. Thus the question to ask is: "What do the grotesque characteristics say about rural Southern society at that time?"
One example of a grotesque characteristics to work with is the image of Addie, laying covered up to her neck, looking like a "nail" under the covers, being fanned by Eula and silently--in a silence foretelling the silence of death--watching Cash use the adze to shape her coffin. What this says about the rural Southern society that Faulkner was exemplifying is that niceties and refinements reflecting protected sensibilities of emotion were not a luxury accessible in that community for their dying community members.
In other words, the delicate protections of dying people from the harsh realities about to surround them are not given to dying people in the rural South that Faulkner depicts in As I Lay Dying. The dying are, on the contrary, face to face with the grotesque realities of death as they lay dying. In addition, Eula's fanning, which is uninterrupted by her flirtation with Darl as he walks through the hall passing the room where Addie lays dying, is another grotesque characteristic showing that not even respect is given the dying in that segment of the South.
It is Darl. He does not look in as he passes the door, Eula watches him as he goes on and passes from sight again toward the back. Her hand rises and touches her beads lightly, and then her hair. When she finds me watching her, her eyes go blank.