Identity is the one theme we find threaded through all four stories in The Sneetches and Other Stories. The Sneetches use tummy stars to assign identities. The Zax base their identities on their north and southbound tasks. The peculiar identity of the empty pants gives the narrator of "What Was I Scared Of?" the heebie-jeebies. The lyrical madness of "Too Many Daves" devotes itself entirely to the identities of Mrs. McCave's twenty-three Daves.
And it makes sense. After all, childhood is all about discovering your identity. And Seuss is all about childhood.
Q: Why can't the Zax just go in a different direction?
A: They are North- and South-Going Zax. Since their identity is wrapped up in the direction they travel, they feel like they can't go in another direction. Maybe we should call them Pigheaded Zax.
Q: Why does McBean pick on the Sneetches?
A: Because he identifies the Sneetches as incapable of learning their lesson. He'll sure be in for a rude awakening if he ever comes back to sell them anything.
Q: Why doesn't Mrs. McCave give her sons numbers?
A: Can you imagine what that would be like? Bad enough being just one Dave in a bushel, but to be number twenty-three of twenty-three would be downright depressing.