Implying that you are the one being logical when all you do is declaring something "factually incorrect" that neither you or I can know for a fact is laughable.
You provided 0 arguments for your position, while declaring anyone holding another position "incredibly stupid". This leads me to suspect that any argument you would have would be purely subjective. My argument on the other hand was objective, I don't even play Alliance so I would never play High Elf anyway.
It is a fact that some people want to be able to select "High Elf" as a race and play as that, even though the character on the screen would be visually indistinct from what they could already play as a "Void Elf". Given that all the art assets and animations already exists, this very limited investment by Blizzard could tilt a customer to decide to stick around for a few more months or return to the game, even if only for a few months before the novelty wears off, because this is something they have really wanted for a as long as the game has existed.
Neither you or I can know for a fact how many such customers exists, or how many such customers need to exist in order for this very limited investment by Blizzard to pay off. Blizzard can calculate the second number, but not even they can know the first number. Reasonably both numbers would be low, so it wouldn't take many such customers existing within the target demographic of tens of millions of people for this to be profitable. Between adding "High Elf" as a race or adding some random leveling quest, likely of similar size as an investment, which do I think would make them more money? The "High Elf" race option hands down.