They are not unaware and it's more than an underlying want to belong, it's an underlying want to be exclusive and special.
When you go Hot pink or think tats on your chest of various patters is a great idea you are pretty much telegraphing that you hunger to stand out as something else so bad that more extreme it is the better.
That's how fashion has escalated. This half shaved hair is born of the fact that short, buzzed and many other rebel styles have hit the norm. The piercings of the face escalated for similar reason.
Most of the people that do that shit do not do it because they actually like it, they do it because they get to stand out more and feel more unique, which in turn broadcast how very boring they likely are.