I mean, all Dwarves are identical because they're all actually all clones of the same 30-something civil engineer. The machine keeps pumping them out, and no-one knows how to turn it off.

More seriously, elves are actually a really weird example to pick, because they literally need half the sleep that everyone else does. An elf has four extra hours every day for extra work or leisure — that's the kind of thing that would have a massive impact on a society. Like, in a world where humans worked 40-hour weeks, an elf that worked 68 hours a week would have the same amount of free time.