NEW YORK (AP) – Why do the Rolling Stones keep playing shows? Because people keep showing up. The Stones played in New York Saturday night in one of the few concerts they’re doing this year to mark 50 years as a band. Mick Jagger told the audience, “You’re the reason we’re doing this. Thank you for buying our records and coming to our shows for the last 50 years.” Mary J. Blige and Gary Clark Junior were guest musicians. The Stones will also play in Newark, New Jersey on Thursday and Saturday.  The Stones are also the latest big-name act to  sign on for next week’s Superstorm Sandy benefit show in New York City. They will perform with other Brit acts The Who and Paul McCartney. Among the others to appear include Alicia Keys, Bruce Springsteen and the E Street Band, Eric Clapton, Billy Joel and Chris Martin. The 12-12-12 show at Madison Square Garden will be available on TV or online to some 2 billion people – and producers say it will be the most widely available live concert ever.