Coordinates define the observation point
Observer latitude and longitude directly enter the conversion from celestial coordinates to local horizon coordinates.
Sources: U.S. Naval Observatory — Computing Altitude and Azimuth
Place names preserve context
A name can carry jurisdiction, historical identity, and timezone context that a bare coordinate does not. It also gives a person something recognizable to verify.
Do not let the label overwrite the point
If a user pastes exact coordinates and the system backfills the nearest city name, the coordinates should remain authoritative for the render. The label is context, not a replacement point.