The world probably will after the technology exists to economically produce it from them. It does not exist today but holds promise of future development.
Actually, several companies are pursuing the development of growing oil-laden algae on a huge scale, which could make it really practical to use the algae to make diesel fuel, heating oil and kerosene, along with ethanol from the waste product. Switchgrass will take longer due to the need to improve the process of making cellulosic ethanol.