Haha that was the same where I was, my girlfriend and I were at the front of GA on Saturday right on the barrier and it was only the two of us and the couple next to us who sang the words, everyone else around us just kind of stood there clueless.

Also I couldn't help but notice the amount of people near me who kept taking their phones out to check texts and Facebook etc the woman next to me literally didn't stop trying to phone her friend, quite distracting really, it does make you wonder why some people go to concerts!.