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.
Not when everyone realizes all the other alternative uses for petroleum besides burning it, many of which are more valuable than burning it.