if there is zero financial incentive to help out the Earth
I would argue that there's a HUGE financial incentive. The company/person that comes up with the "next big thing" in fuel sources is going to be incomprehensibly wealthy - I think that much is clear.
and it's cheaper to keep doing it
I think supply and demand almost guarantees that it will not always been cheaper. Maybe not on an acceptable timeline, but, its obvious that at some point it will become prohibitively expensive to continue to use fossil fuels.
I also feel like your rich people reference is sort of a catch-all FUD argument. Oh no, those terrible rich people are causing all the problems. There are plenty of people on this very forum that are probably rich by most standards. Surprisingly, that doesn't make them faceless evil monsters.