If you mean bringing a sign don't that is just inconvenient for a concert. If you mean the musician signing things it is up to them, so you will have to read about that specific concert.
I've been to the ballroom for a concert. If "sign stuff" means making signs they don't do that.
Im not sure what you mean by the sign stuff?
Rephrase the question, please.
Sign stuff? What do you mean
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