Shadowboxing Steelers Fan Is The Weirdest Steelers Fan

I...I don't get this.

I mean, I understand that dressing up like an idiot and acting like a weirdo are things that a lot of football fans like to do, but I can't for the life of me figure out what this guy's angle is. What does boxing have to do with Pittsburgh or the Steelers? What the hell does a feathery headdress have to do with boxing? And is that a lei? That looks like a lei. Why is there a lei?

Thanks to John for the video.