How do rockstars get away with wearing ridiculous garb that would be mocked anywhere else?

Such as Boston .

Kiss, Marilyn Manson, the weirdos from System of a Down…the list goes on. People on the street would be laughed out of the town were they to wear anything like it… what makes it so special for a musician? How much of that is a musician’s free spirit.. and how much is just… odd?

How do you explain this phenomenon of fashion?