The Minnesota-based arena rock tribute band Hairball prides itself on near-identical portrayals of icons like Alice Cooper. So when a white vocalist appeared wearing dark makeup to play Prince's "Purple Rain" to a crowd of 7,500 at the Minnesota State Fair recently, it was business as usual, said their manager Mike Findling. "They wear makeup on KISS. They wear makeup on Alice Cooper. They wear makeup on Prince," Findling said, adding that he didn't consider the powder vocalist Kris Vox wore to look black to be blackface. "How would we do it in any other way?"