Morals in these stories are shown by changes in character or moral decisions that are taken by both of the major protagonists in these short stories. Consider how Roger in "Thank you M'am" changes dramatically in his personality, becoming a better person thanks to the meeting he has with Mrs. Jones. He starts off as an isolated and neglected teenager who turns to crime to gain what he cannot afford to get. Mrs. Jones, by taking him home and showing him love, affection and generosity, makes him realise how bad what he did was, and he improves morally as a result.
Likewise, the barber in "Just Lather, That's All," when he has the opportunity to kill the military leader that his rebel group is fighting against, comes to a moral realisation of his place in the world:
I don't want blood on my hands. Just lather, that's all. You are an executioner and I am only a barber. Each person has his own place in the scheme of things.
Having had the opportunity, he realises something intrinsic about who he is and his own moral base, and leaves this experience a more self-aware individual.
Thus both stories deal with the protagonists' moral growththrough interactions with others.