Someone pointed out to me that “wherefore” in old English actually means “why.” That’s not to say that Juliet is asking about Romeo’s parents picking out such a silly name (versus Hamlet, Othello, Lear, etc.). She’s a member of the Capulet family and is bemoaning that he’s a Montague—if Juliet’s family caught them during a romantic encounter, they’d lock her in a closet and gut Romeo like a trout. Wherefore, you might ask? Wherefore not?
You are. And that is enough.
