>Since they all have to identify themselves to the FCC with these call signs, it's convenient to advertise the channel with that name as well
Not just that, it's required by federal law to announce the callsign once an hour, in both radio and OTA television. https://en.wikipedia.org/wiki/Station_identification#United_... (If you watch sports broadcasts on OTA TV you might notice a subtle overlay pop over the content at the top of the hour)
Made more sense in the analog era, when tuning was done by twiddling a potentiometer and you never quite knew exactly what frequency you were on.
Though the identification you hear may be that of the originating station in the case of a simulcast.
Many years back Clear Channel would simulcast hurricane coverage across most of their stations in Florida, resulting in them all identifying as "Newsradio 610 WIOD Maimi". (Though a YouTube search suggests iHeartMedia now pitch- and speed-bends to say all the legal identifiers very quickly.)
Not just that, it's required by federal law to announce the callsign once an hour, in both radio and OTA television. https://en.wikipedia.org/wiki/Station_identification#United_... (If you watch sports broadcasts on OTA TV you might notice a subtle overlay pop over the content at the top of the hour)
Made more sense in the analog era, when tuning was done by twiddling a potentiometer and you never quite knew exactly what frequency you were on.