This is of course all speculatory, but I think for many of us the things that sets him apart from the "money-focused" crowd are his goals and how outspoken he is about them. He wants to get people to Mars, which as a business venture will not turn a profit in his lifetime. I'm not saying he is altruistic but rather that he might be more of the 'fame and glory' type, wanting to leave a larger mark than a big digit in some future Wikipedia bio.