I can't remember this science fiction short story.

In this short story, there is a man who does not fit in with society. He starts noticing people who always seem to fit in, and follows one. As the story progresses, he learns more about these creatures; they transform so that they always fit in, they create money and draw it from flaps of skin. By the end of this story, the protagonist becomes one of these creatures.

Can anybody help me figure out what this short story is?