Big money has gone into other fuels.
It's very very hard.
Batteries have consumed vast amounts of dosh, and yet in the last century have improved hardly at all.
Hydrogen is dangerous stuff, as is methane and anyway they need to come from somewhere.
Contrary to those of us who've seen too many Hollywood movies, it's midly hard to get petrol to explode, and it's not very toxic.
It's energy density is high, and there is deep experience in handling it.
Even at it's relatively high current price, everything else is much more expensive, usually less green and frequently dangerous enough to be used as a disaster in Thunderbirds.
Biofuels are horribly un-green, quite possibly the most environmentally damaging energy source known.
Car firms produce what people will buy.
They've tried to sell little cars and failed.
They actually don't care what they sell, and the margins on BMW minis sold in the USA are vastly
more profitable than gas guzzlers.
But they are niche vehicles.
If consumers wanted 60 MPG vehicles they could have them. But they would be slow and the size of "Smart" cars.
It's not the car makers, or the oil firms, it's us.
It's dishonest psuedo liberal gesture politics to blame car and oil firms.
It's us.
You want better cars then you are going to have to pay more for a car that goes slower and has less elbow room than a British train a ruch hour.
The car makers would love to sell you these.
Not because they are good people, because often they are not, but because they want your money.
Ford's biggest competitor is not General Motors or Honda, but the huge number of cars in use. If people upgraded from old inefficient cars to new ones, the car makers would lurrrrvvee it.
But you don't do you ?