In "The Life You May Save May Be Your Own," who is worse, Mr. Shiftlet or Mrs. Crater?

In a moral sense, Mrs. Crater is the worse of the two. As the mother, it is Mrs. Crater's responsibility to look out for her daughter's well-being; this responsibility is intensified because of Lucynell's multiple vulnerabilities: deafness, muteness, and mental deficiency. Mrs. Crater essentially sells her daughter for $17.50, a broken down car, and a place for Shiftlet to stay. Though Lucynell is in her thirties, Mrs. Crater lies to Shiftlet, signaling that she would hand off an underage girl to him: "How old is she?" Mr. Shiftlet asked casually. "Fifteen, sixteen," the old woman said."
Shiftlet's behavior is also despicable, but less so, since he isn't using his own flesh and blood as the stakes in a symbolic poker game. He is simply a drifter, opportunist, and con man, and so his abandonment of Lucynell and theft of the car are hardly shocking. His hypocrisy at the end of the story is therefore laughable when he prays, "Oh Lord!" Break forth and wash the slime from this earth!"