It's an unfortunate flipside to their willingness to work so hard-- they almost need to believe in the impossible to keep up the pace. Ideally there is someone between them and the public face of the company, but all too often they can't help spouting off stuff they should be keeping under wraps in front of TV cameras or in tweets.
It's like there is this enormous gulf that most others can see, but to Elon it's invisible.
So don't let anyone tell you that philosophy and theology don't matter. We are witnesses a multi-billion dollar bet being made on the basis of some extreme views about the nature of man, and because this appears to be a core belief of Elon, I doubt he will ever update his priors to make more effective investment decisions based on feedback from real-world tests. He will always view this as a project that is almost-ready with just a few technical glitches to overcome.
The reason why he's so motivated is because his compensation package is so ridiculous.
If he is so uninterested by money he can of course show that by giving it to charity.
18 hour days are the "walking barefoot in the snow for three days" of our time: https://en.wikipedia.org/wiki/Road_to_Canossa
Amazing how neither sleep deprivation psychosis nor frost bite are a thing if you're rich enough and talking about how virtuous you are.