I live in a community that is considering such a move. A neighboring community has already banned them with strong support from merchants. The issue at hand is that large numbers of such bags have been turning up in recent years in the salt marshes that line the Long Island Sound, two rivers that pass through the community along with smaller tributaries, and in trees. Like many local communities, the town has been experiencing fiscal challenges. It is also subject to New York State's 2% property tax cap (likely to be waived this year by a vote of the Council on account of pension/health costs, especially as a poll of local residents strongly supported such a move). The efforts to remove the bags from the trees, streams, and marshes impose costs on the town.
One alternative would entail spreading those cleanup costs to the merchants issuing plastic bags (allocated based on approximating their share of the bags). Grocery stores already have thin profit margins and a relatively elastic demand curve would make it difficult to pass a large share of those costs to consumers. Not surprisingly, that alternative was not considered.
Another alternative would entail levying a fine to the merchant whose bag was found. That would be unfair, as it isn't the merchant's fault that someone improperly disposed of their bag. In practical terms, it would lead to bags being unmarked. That alternative would not be viable and it wasn't considered.
Another option is doing nothing. Under that option, the town would finance the increasing clean up costs and, given the long-term fiscal issues involved (ranging from pension/health costs to future reductions in state/county funding that appear likely on account of their fiscal challenges), by reducing other services and/or raising taxes. The survey on waiving the tax cap revealed very little support for reducing police, fire, first responder, etc., services.
That leaves idea of banning plastic bags. The costs to merchants associated with issuing substitute bags were a ban implemented would be very small. That estimate is based on the experience of communities in the Tri-State area that have banned plastic bags. Under the ban being considered, one would not be required to have resusable bags. Merchants would merely use paper or other plastic substitutes, paper being the overwhelming choice from what I've heard. There would be exceptions e.g., for certain packaged foods.
In the end, the issue really has to do with pollution in this local case, not a desire to be "green" for the sake of being "green." There is no desire for the town to dictate to its residents how to lead their lives, but a desire to solve what has evolved into a real problem. If others have better ideas for addressing the pollution problem described above in a fashion that shields the town from growing clean up costs, there is a comment period available before the legislation is taken up. If the experience is similar to that of the neighboring community that adopted the ban about a year ago (and by a unanimous vote among a Republican-majority Council), no such alternatives will be introduced. Instead, the ban will be the position that enjoys the largest share of public support.