Tools of Characterization
The descriptions of Minnie skimpy dresses and see-through underwear make most readers a bit uncomfortable. They help characterize her as vulnerable, and as a person who idealizes her unfulfilled youth. She wants to be like the people she sees in the movies and like the young couples she sees on the street. She might be thinking that if she can dress like them, perhaps she can be like them. This seeming shallowness stems from a perceived lack of options, or imagination. Much like Emily Grierson in Faulkner's " A Rose for Emily " Minnie is paralyzed within a society that finds her useless and scornful.
When we see how McLendon treats his wife, his image as a bad guy is reinforced. This story would have been much different, and even more puzzling, if McLendon was shown treating his wife lovingly. By showing him as an abusive husband, Faulkner seems to be making the point that if a person is violent in one area of his life, he is probably also violent in others.
Minnie's home life doesn't sound so bad. Sitting on the porch for hours; the mother alone in her room; the aunt taking care of the house and such. But, this isn't what Minnie wants. As the town has made abundantly clear, an unmarried woman, living with her family, must have something wrong with her. Her home life then is a source of shame, and a symbol of her failure. It also points to a lack of imagination and wasted potential. Like many trapped women before her, Minnie could have at least tried to find a place for herself in the community with positive works, or she could have moved. Instead, she chases the seemingly impossibly dream of marriage and family life that the town dictates is necessary.
It's also interesting that the story provides no details on the family lives of Will and Hawkshaw. Why might Faulkner have chosen to omit such details, while providing them for McLendon and Minnie? Maybe to emphasize that the ideal of marriage and couple-hood that Minnie has been denied often isn't all it's cracked up to be.