Without a doubt, Le Guin's purpose in writing this horrifying story was to cast a subtle spotlight on the injustices of our own society. While no town in the world has full happiness and no child is locked away in a closet to ensure the happiness of everyone else in their community, there is much injustice in our world.

The child locked in the closet is a metaphor for everyone who is treated unfairly and spends their life working towards the happiness and comfort of others without every feeling these things themselves. Consider, for example, a street sweeper who works from sunrise to sunset to clean the streets for residents of a wealthy neighborhood without ever having the money to be able to send his children to school.

Consider the plight of refugees around the world, forced by the threat of violence to leave their homes and seek their fortunes elsewhere only to be greeted by red tape and hostility. The child in the closet could easily be argued to represent refugees.

The story could even be a criticism of capitalism as a whole and a free market system that enables some people to become rich while subjugating others because of factors such as their lack of access to education.