"White "Christmas" was so popular that Bing had to re-record the song five years after the original 1942 recording because the original masters had been worn out from all the pressings. This is the version that became a holiday tradition.
Who writes a song about a name they found in a phone book? That's just one of the everyday things these guys find to sing about. Anything in their field of vision or general scope of knowledge is fair game. If you cross paths with them, so are you.