alt Hacker NewsI don't understand because I'm not American but how does New York the city have such powers? At least where I am, cities aren't really "real" in that they are constructs the provincial government creates (and can uncreate). A city here could never make such a ban.
Cities are similarly not "real" in the US, but there's a strong tradition of local governance, so some states (including New York: https://www.nysenate.gov/legislation/laws/MHR/10) issue blanket authorization for any city to pass any law that doesn't contradict the state's general laws.