Whether one is for or against charging for bags at grocery stores, the concept that imposing such a regulation is an illegitimate extension of government is incorrect. The functioning of free market capitalism is predicated on the assumption that individuals bear the monetary costs associated with their behaviors. There are real costs associated with the production, distribution and disposal of bags. The fact that there is currently no fee imposed is an example of what is generically referred to in economics as the "tragedy of the commons." In this case, the "tragedy" is that it is in everyone's overall interest that we not overuse grocery bags since they add to the cost of groceries, and impose a cost of waste disposal, whereas it is in each individual's interest not to go to the hassle of keeping their own supply of bags and bringing them to and from the store. Currently people who bring their own bags are subsidizing those of us, such as myself, who generally do not. To make capitalism work efficiently, one legitimate role of government is to devise rules that eliminate "tragedy of the commons" situations. In terms of what is legitimate government function, the only question is how much one should be required to pay for a bag, and not whether one should have to pay for it.
Steve Mark, Breckenridge