Elves have always been something of the "pet favorite" in D&D. There seems to be more game mechanics and fluff text in favor of elves in many D&D settings.
Elves more variant sub-races and class versatility: it's plausible to many gamers for elves to be fighters, wizards, druids, etc. Since when's the last time you've seen wizardry encouraged among dwarves in a setting? In 4th Edition, we have three "Elf" races: Elves, Half-elves, and Eladrin (who are now celestial elves). Also, elves in some sourcebooks are considered kin to the Fey and have a bond with these powerful creatures. Can the same be just as readily said of Halflings, Dwarves, or Humans with some other powerful species?
In many settings, elves had the mightiest empires, the greatest magic, and the most beautiful people. In Forgotten Realms, the Races of Faerun entry on Sun Elves reads like some kind of nationalist propaganda. Sun Elves pursue perfection in all its forms no matter the vocation; all sun elf communities live in harmony with nature and can get wild animals to help them (despite having no racial stats to accomplish this); sun elves have the last secrets of Mythal creation and Elven High Magic (only the humans had racial-specific epic magic prestige class, but they learned their magic from the elves). Most Sun Elves are Chaotic Good, but a significant portion of their population hates humans and views them as vermin, with some fringe factions (supported by some elven nobles) advocating genocide. Due to poor relations with humans, many sun elves will refuse to save the life of a human even if said elf faced minimum personal risk.
In Dragonlance, the Silvanesti Elves are xenophobic, reactionary racists who view even other elves as uneducated savages at worst and impoverished elvish equivalents to hillbillies at best. The 3rd Edition Dragonlance setting went so far as to describe this view as "Good alignment taken to extremes."
These two examples are cultural sub-races representing the "haughty elf perfectionist xenophobe," yet it seems to be a double-standard because any other sentient creature would probably be branded "non-good" alignment-wise due to their persistent intolerance towards everyone else.
Why the special treatment? Why the exaltation in flavor text and character options? Is it due to the perceived omnipotence of Tolkien's elves, of which D&D elves were partly based off of? Or do we just like pointy-eared magical people?