Mercurius
Legend
I think a lot of this has to do with how deep one wants to get into immersion. Playing a truly non-human character is difficult, and most films and tv shows aren't really all that good at doing it. Some (most, I would guess) people just want the imaginative fun of playing an elf or a dwarf, but don't really care about the deep psychology of it.I will say I have noticed a division in previous conversations (not just here) between those who want high-concept races and those who are satisfied with the differences being basically cosmetic. I feel a little mismatch between myself and one of the GMs I play under because when he designs custom races, he goes for the high-concept, and I sometimes find them more stifling than liberating to play.
It's just a matter of taste.
The archetypal Tolkienian races were different enough to be, well, different, but close enough to be relatable. Elves are more angelic beings, Dwarves more earthly, and halflings more domestic. But they all portray different aspects of our own nature.
Or we could look at Star Trek. Vulcans are basically humans with far more mental development, but at the expensive of emotion. Klingons are the reverse: more emotion, less mental. Romulans are kind of like Vulcans whose mental nature has been twisted by psychopathic tendencies, and perhaps why the Vulcans work so hard to remain "pure."