I agree, the costume contest was a bit awkward. It wasn't well organized at all, wasn't properly advertised and was mostly improvised. Now, it wasn't a professional fashion show either: we're just a bunch of nerds, either gamers or software developers, we're here to have fun and we don't care. I was there, I had fun, I don't care.
If you think it sucked, you're welcome to show up at Minecon 2013 and show us all how great you are.