Given the sheer number of fight videos floating around online, there needs to be something particularly notable about the bout in question for it to get any attention.
This video originally gained traction because it features a girl getting hit in the head with a shovel. It's an obviously fleeting moment that can be viewed on repeat for eternity thanks to the magic of Vine. If you want to be entertained, that's the clip for you -- if you want to be mesmerized, then you'll want to check out the source material.
You could analyze every single frame of this video and conduct interviews with every single person involved, and I still don't think you'd ever be able to figure out exactly what happened here. I don't think these two girls wanted to fight each other in the first place. Their in-fight banter sounds less like fighting words and more like two people who don't know how fights work.
Take, for example:
Girl 1: You better quit hitting me in my face, bitch. Girl 2: That's the point! It's a fight!
It's also worth noting that the girl who got hit in the head with a shovel only had it happen to her because her opponent went to grab a BB gun from her house -- after the soon-to-be-concussed combatant demanded she go get it.
Middle America is a wild place.