I dated a girl in high school who used to chew her toenails, and I used to tell her the same thing I tell Zoey now: That's not very lady like behavior. But unlike my girlfriend, Zoey sharpens hers to be razor sharp like a cat's claws.
Yesterday I clippy'd her claws, and today she's sharpening them. If they get too sharp between clippings, then I can just take the points off them with the clippers. In many ways, Chihuahuas are more like cats than they are dogs. Highly intelligent, scheming and manipulative team player cats.