The thing is, when you see a 60 year old with bright pink spiky hair, your first general impression is of someone who could never accept that their teenage years were over, even teenagers know that in their hearts.
So let 'em wear radical styles and stupid stuff while they can still get away with it. feeling you're free to express yourself isn't just, supposedly, a requirement of who we are, it's actually an incredibly good way of getting the best out of your employees, if schools and industry would get their heads out of the 50's and concern themselves more with the quality of their product and less with their sphere of influence.