"Von Neumann is remembered as a man of warm personality: courteous, charming, and jovial, with an often ribald, sometimes wry, sense of humor that made him excellent company and gained him a reputation as a bon vivant. He was fond of limericks and practical jokes and hosted frequent Princeton parties. He was also well known as a reckless driver, once emerging, so the story goes, from a smashed car with the explanation: "I was proceeding down the road. The trees on the right were passing me in orderly fashion at 60 MPH. Suddenly, one of them stepped out in my path. Boom!""
I suspect the majority of genuii are self absorbed. Certainly that aspect of (mis)behavior is a mainstay of the genius stereotype. Or maybe that portrayal in movies is just the conceit of lazy scriptwriters...