The na ... toe construction is actually not that comon with place names. It's much more common with pronouns - e.g, Ek kom na jou toe [1SG.NOM. come to 2SG.OBL. to], i.e. 'I'm coming to you', where it is impossible to drop the na, although toe is still dropable. In the place-name context, na ... toe is really just a minority alternative to toe.