It's because you and I choose to see certain sides of them that irritate or endear us to them: you see Bono as a "tax-evading ego maniac" (I see him as working in his own manner to address/highlight/ alleviate the suffering of millions) and I see Ehrenreich as a scientist pomo basher (and you see her as a journalist). We do differ: I see Ehrenreich as equally well-minded as Bono or any other humanist (and me, FWIW), despite her silliness or style, whereas I suspect you have no such view of Bono.
--ravi