While it's easy and convenient to blame the "oil companies" for every ill the nation has, the fact is capitalism, and the free market will dictate the course of any transportation system. The profit margin of the "oil companies" is one of the lowest of any industry in the US; they accumulate record profits through volume, not pricing. Is that so surprising? They do not receive any tax breaks that other major industries do not receive and they are not operating outside of the restraints of law. If they were, then they should be prosecuted as any other criminal enterprise should be prosecuted. The "oil companies" remain the rhetoric target of those that don't understand capitalism and the free market.
Of course they support the use of their products through automobiles and buses, wouldn't you? The question is; if there is something better in the terms of efficiency and price...well; where is it? Competition is the lifeblood of commerce. Until there's a better transportation option, the "oil companies" will reign supreme.
Frankly, I'm a bit disappointed in the way you continue to regurgitate the rhetoric you have been fed. Big Oil is not the problem, except to those that refuse to do the research and chose to follow the party line.