It really depends on the band that's playing...there's one particular band where if the lead singer sees either a shirt with a picture of or a make-shift hair-do from a certain very popular ex-guitarist he will immediately stop playing, leave the venue and the city and that's it. I've worked one of those shows before and that was what the production staff for this band informed us of, adding to the fact that the lead singer had done it twice on that particular tour already, so as security if there was anyone that we saw that filled the bill it was lose the do and flip the shirt inside out.