It's the Pakhtun's personal choice. And not his choice too.

Like if you want the permanent residential certificate you must own property in Karachi. Pakhtuns on the other hand live as tenants and most in Goths (Which aren't leased, not legal houses).

Plus, I being a Pakhtun in Karachi know that it will be vary hard for me to get back home very early still I won't like to loose voting rights in Pekhawar, as after all it will be Pekhawar giving a few feet of it's land to my dead body.