I'm a (purgatorial) universalist in the first place, so the idea of "sin = hell" isn't something I subscribe to. We all sin. We're all going to make it, in the end. But we should try to sin less. Excess wealth is sinful, and being a billionaire is completely incompatible with Christian doctrine. That sort of social wealth disparity simply didn't exist at the time of Christ, with the exception of, say, the Roman Emperor himself.