I think that every CD sold for a band is one that isn't sold for some talentless moron who just ripped off some classic and put either
a) a talentless bit of talent singing on the video or
b) a frog going "ding ding" a lot over the backing.
I occasionally see children wearing "Nirvana" t-shirts... I think "Thank goodness they're listening to proper music!"... then I suddenly realise they were probably born after Kurt died!