It's not that in well-functioning societies there's no need for paternalism. It's that in well-functioning societies the government can be trusted with enough power that they can carry out the kind of modestly paternalistic agenda that people like me favor. Similarly, in well-functioning families parents can be trusted with enough power to do modest, reasonable parental paternalism. Naturally, in poorly-functioning societies/families the government/parents seize power anyway, but we're talking abut what's legitimate, not about what actually happens.