DAMN! That was the night from hell! I have never seen anything like what you described happen ever. When I was in college, I know that two fraternities had a beef with each other. They had one fight and it was over. IFC or IGC intervened and put an end to it immediately. This type of conduct is completely unacceptable and should result in some sort of punishment.
I hope that you find your shirts. Maybe you should check out e-bay.
