Having control over the energy source gives you a lot of power. It doesn't make sense to give up all that power right now. We have to wait until holding on to this power is more expensive than letting it go and this can take a long long time.
What you call the "oil" industry is really the energy industry, and they really don't care which way things go as far as climate policy is concerned. They're set up to make money either way. Who do you think all those government grants for "renewable energy" research go to?
They absolutely care. If renewable energy catches on, the values of their oil reserves will plummet. That's why they continue to fight against any reduction of emissions.
The value of the uses has nothing to do with the value of the petroleum. If we stop burning it, demand falls off and the price drops. Dramatically, because if we stop burning it then we have way more than enough for all the other uses.
That's actually the primary reason we need a carbon tax -- if we make any real progress toward replacing oil in some other way then the partial progress causes the price of oil to fall and interfere with additional progress.