Why not take this idea a bit further?
We all have ID cards and whenever we go into a gig to perform or listen we scan them through a reader. Come to think of it, whenever we go into any public building we scan them. Then Big Brother will know exactly where we are and where we've been at any time. Anyone who attended too many subversive events like Billy Bragg concerts could be more carefull monitored.
The PC police would also be able to monitor gigs for ethnic balance and anything that was too "white" could be closed down.