✔ 最佳答案
Mostly because the tree-huger environmentalists won't let the oil producers go after the huge reserve deposits in remote areas like in Alaska and off-shore along our coasts. Even if we could go after ALL the oil reserves, the oil isn't just laying around free for the taking. It costs money to explore and drill for the crude oil, then more money to transport it to a refinery where is is converted into diesel fuel and gasoline, and then even more money to transport again to the retail outlets where you buy it to use in your car.