Though breaking up is said to be hard to do, getting back together appears to be much easier. At least in the world of rock and pop, where reunions are de rigueur and often translate into big paydays. Akin to what happened with the stigma associated with artists who license songs to advertisements, the cynicism that once greeted reformations has faded. The notion of “selling out” by staging a reunion now feels as antiquated as the cassingle.