Why not Sam as an 'Elf-friend'?

[Lotrelf]

Both Bilbo and Frodo get the honor for their love and service to the elves; Sam despite his childish nature loves the Elves as much, and does great service bearing the Ring(for a while). His service is acknowledged and he is allowed to go across the Sea. But he does not gain the title of Elf-friend. Is there anything Professor Tolkien wrote in his letters about this? I don't remember anything from the books.