I generally go with the flow in these situations - if the people around me are standing/dancing, I will too, but if nearly everyone is sitting, I'll sit down. At that Allman's show I went to on Saturday night, we were sitting beside one of the most annoying, drunkest concert-goers we've every encountered. At first this woman insisted that everyone sit down. Then later in the show she stood on her seat and wondered (loudly) why everyone else was still seated! Then she kept yelling "Get the fuck up the piano" over and over again. Apparently she wanted Greg Allman to get up and walk around, and be front-and-center on the stage! Toward the end of the show this dimwit realized that Dickey Betts was no longer part of the band - "Where the fuck is Dickey" she kept yelling.