I can't even remember life without a towel wrap, but I will try to provide a scenario which makes clear why absolutely everyone should own one. You just get out of the shower; dripping everywhere you step; you try to roll the towel so it stays put as you brush your hair, brush your teeth, put on deodorant, apply make-up / shave and pick your outfit for the day. You lost the towel at step one, and obviously the blinds are open so you can give your neighbors/roommates a little show. Instead of spending the next 10 minutes readjusting the towel and shimmying so as to not loose the towel, you could have just velcroed on your towel dress and continue getting ready for another day at your desk.
Some might ask why not wear a bathrobe? Because bathrobes are for your dad, and they make you sweat especially as you are blow drying hair negating any deodorant application. Added benefit: All your friends will be jealous.
And no it's not just for girls.