People are making the argument that night elves are darker because they live in moonlight/nighttime and blood elves are lighter because they live in sunlight/daytime.

You can make that argument if you really want, you can say Azeroth is a fantasy and doesn’t follow real world biology, but know that ALL aspects of WoW (in fact all fantasy worlds) are rooted in the real world.  

World building does not happen in a vacuum. 

So ok, there are pinkish, lighter skinned night elves.  Why couldn’t there also be darker, deeper colored blood elves?  This is magical biology we’re talking about here – we’re already making shit up.  Why limit ourselves?

And blood elves can apparently tan so their skin DOES react to sunlight by getting darker.  10000 years in the sun without anyone getting more than a light tan?  I dunno. 

It just seems to me that if a night elf can have really light skin, a blood elf can have really dark skin.  

Uncomfortable how eager people are to exclude others even in imaginationland.  

That is literally the opposite of the way it works with skin color in the real world anyway.