Not to display my rampant bias (as if I would ever do anything like that
) but it seems to me that being an elf-friend is something that is restricted to Men or Mannish creatures (read hobbits). At least I can't recall a time when, oh, just to pick an example, a dwarf was called an elf-friend.
On the providing service to the Elves front, going back to the First Age, the Dwarven kings of Belegost were always faithful allies of the elves and saved their bacon at the Battle of Unnumbered Tears. However, Azaghal was never bestowed the title of Elf-friend posthumously.
Although, I must admit that this post is based to an embarassing degree on pure unreasoning first reaction. I'm not sure, but there might be a reference that I'm forgetting.