Why does Macon watch Pilate, Reba, and Hagar singing, but from a position outside, in the dark, where they cannot see him? Why does he not enter the house? What effect does the experience have on him?

Macon disapproves of the way Pilates lives. He stays outside because her living conditions disgust him.... not only the fact that she lives in a slum, but because neither she or her daughter had ever married. He is mesmerized by their singing, but he doesn't make himself known. He is ashamed of his sister, her appearance, and her participation in alcohol smuggling during prohibition.