LOL, hutch!
seriously tho, there is no dress code. wear tight pants or sweat pants - up to you.
the concert is sold out so you'll be two of 1200 people packed in there... it won't be like a dance club where there is a lot of space to see and be seen. personally i'd dress for comfort (running shoes!) but i'm certainly no fashion plate so what do i know.
eff it. wear miniskirts.