Not only the above localities have banned the plastic bags but the entire state of Hawai'i was the first to enact the ban in the US. It will not take long for that to catch on in other states.
The simpler solution would be to not litter but that is asking a small percentage of the public too much. Unfortunately, all too many times do they blow out of the back of pick-up trucks, out of garbage cans, etc.
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