To be totally fair, my own vamps (as I currently have them figured---it's a WIP) have a similar healing gig where their body always returns as soon as it can to the way they died, which includes hair always growing back a la Anne Rice...of course, this includes hair on legs, underarms, etc., not just head-hair on dudes. Of course, from LKH's POV, I'm sure that short hair on a man is the same as a grievous physical injury.