I've seen people playing half-elves in our games for various reasons: character concept, roleplay ideas, cool factor being the most common.
I have also seen someone choosing half-elf over elf in order to play a multiclass combo (if you eliminate multiclassing penalties and then find that half-elves have not a single advantage, then it's your problem) without completely changing their background to that of a human.
All this in 3.0, without even the extra crumbs that 3.5 tossed to half-elves.
I agree that if you look at the list of racial bonuses, they definitely get less than the other races. But...
1- Many times people don't even use most of their racial bonuses (many dwarves just happen not to ever have a chance to use stonecunning, or to ever fight a giant)
2- Racial bonuses are much less important than class features, and become even less important the higher you go in level
IMHO, many players just like to think in terms of numbers, and because of this they may never want to play a half-elf. Not too bad, since this kind of players anyway roleplay everything in the same way: the very_elaborated "want to get more rich & powerful" character concept, sometimes with a variation like "want to become able to kill the gods" or "want to force the DM to use epic rules".