Playing devils advocate, they probably strop the edge twice a day with a leather strop or a super fine grit whetstone. This isn't really sharpening as such, ver

Playing devils advocate, they probably strop the edge twice a day with a leather strop or a super fine grit whetstone. This isn't really sharpening as such, very little material will be removed from the blade (as you probably know), but to an observer would appear to be 'sharpening' and would theoretically assist in maintaining the very minor burrs that would occur from daily use on hair, if the scissors have some bypass this may also be desirable as a burred edge can interfere with the bypass action. Caveat, am an Amateur bladesmith, not hairdresser so I don't actually know much about scissors specifically and dont have a frame of reference for how much damage hair does to an edge.