Justin Bieber Summerfest Marcus Amphitheater June 27th

Justin Bieber will perform his three popular songs on June 27th at Summerfest. This one has me wondering what the heck is going on with the booking of Marcus Amphitheater shows. I understood the two night Petty fest. I understand the three nights of country music, seeing that the Waukesha republicans need someone to see at Summerfest. Really? Justin Bieber as a headline act?