Look what happens to the use of plastic bags used by grocers and restaurants when you require the merchants charge five cents per bag. This is a big win for the environment:

In its first assessment of how the new law is working, the D.C. Office of Tax and Revenue estimates that city food and grocery establishments issued about 3.3 million bags in January, which suggests a remarkable decrease. Prior to the bag tax taking effect Jan 1, the Office of the Chief Financial Officer had estimated that about 22.5 million bags were being issued per month in 2009.