Elon was irritated that he was behind in the AI intellectual property race and this narrative created a perfect opportunity. Not surprised in the end. Tesla effectively did the same thing - "come help me save the planet" with overpriced cars. [Edit: Apparently Elon has left OpenAI but I don't believe for a second that he will not participate in this LP]
I agree this isn't a non-profit any more. It seems like that's the goal: they want to raise money the way they'd be able to as a normal startup (notably, from Silicon Valley's gatekeepers who expect a return on investment), without quite turning into a normal startup. If the price for money from Silicon Valley's gatekeepers is a board seat, this is a safer sort of board seat than the normal one.
(Whether this is the only way to raise enough money for their project is an interesting question. So is whether it's a good idea to give even indirect, limited control of Friendly AI to Silicon Valley's gatekeepers - even if they're not motivated by profit and only influencing it with their long-term desires for the mission, it's still unclear that the coherent extrapolated volition of the Altmans and Khoslas of the world is aligned with the coherent extrapolated volition of humanity at large.)