Whatever source of information they're using for city/town is definitely flawed. Looking at what they have for Rhode Island there are definitely municipalities missing, but then there are also entries that aren't cities, towns, or counties. For example, "Newport East" is an area inside the Town of Middletown. Similarly Narragansett Pier is an unincorporated village in the Town of Narragansett. Neither have their own zip code or anything. Meanwhile the town of Glocester (home to 10k people) is entirely missing from the list.
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