Concerning Elf-friends

[Fingolfin II]

And why, praytell, are we not obliged to serve the elves?

While Elves are the greatest beings of ME (not including Maiar), they are the friends of Men, though they did teach them a lot. Felagund first found Men and 'taught them true knowledge' (hope I got that quote right; don't own a copy of the Sil.), and Beor served him as several Men served other Elves (i.e. Hurin and Huor "served" Turgon).

However, I don't think Men are obliged to serve the Elves because in the end, I suppose it is a matter of "free will", the gift Eru gave to Men to shape their own lives and change the course of the future themselves. An analogy is Men and horses- are horses obliged to serve us, since we are more intelligent than them?