Q: Why do elves have pointed ears?
A: Well, there has to be some point to elves...
Tolkien elves rock, though. The Silmarillion kills them in their droves - divine wrath, battle, poison, immersion in arctic ice, dragonfire, balrogs, treachery, evil dwarves, more balrogs - subjects them to all manner of awful tortures, turns family against family and then smashes all their kingdoms into little bits and sinks them beneath the sea.
Don't like the super-shiny, super-flawless D&D elves, though. Rather laughable, really, and not at all convincing as a racial group. In my main homebrew (the 18-year monster), elves were very much akin to those Gothmog described: conspiracy-laden xenophobes trying to keep humanity knuckled under in the mud, where they belong. Probably with good reason, but not very nice all the same.
I love the Dark Sun elves, though - a really innovative twist on a fantasy trope. The "standard" elves left on Athas in Sylvandretta all of a sudden are much more resonant.
The next incarnation of my big homebrew does not feature any of the PHB races apart from humans, and they have been tweaked and altered a fair bit as well. These days it just seems to me like elves are somebody else's idea, and an old one at that.