You might remember the alt-rock band The All-American Rejects and lead singer Tyson Ritter from their handful of turn of the century hits such as “Dirty Little Secret.” As University of Missouri seniors graduated this spring, the band played the latest in a series of pop-up shows it’s been doing at people’s houses. We hear what the band, concertgoers and even the police think about this diversion from the current era of arena concerts.