I remember the taller barber in your photo. Like many people, I didn't go inside but stood out in the promenade and gawked. For some reason I think the barber shop is run by the same vendor who does the spa treatments. I thought I heard that barber speak with a British accent.
Linda - I'm sure they are not traditional barbers, but more likely trained hair stylists or beauticians playing barber. I did see the whole treatment though - the hot towels, men getting shaves, etc. The barbers had order pads and wrote down what the person wanted before starting. No doubt to ensure the cruise card was properly charged!