Hoods are lightweight for several reasons. They do not do much more than cover the engine, like help structurally in an accident, so they don't need to be heavy. Also, the engine area is already heavy enough without adding more weight to that area, further driving down fuel economy.
Drift cars are usually light weighed cars with the ability to "drift" while maintain control. Not all cars are allowed in drifting competitions, nor are they suitable for drifting. However, these "drift cars" are.