The alliance sendt the blood elfs on a suicide mission, that is why they don't want to be in the alliance.
That there is alliance high elfs in Stormwind alone kind of goes against the lore

As a devoted member of the Horde. We don't want you metro-elves either. Give the Alliance High Elves!

It doesn't go against the lore, it is well known that the High Elves still exist and oppose the Blood Elves, and never joined them. They are noted for glowing blue eyes as opposed to green, which is Warcraft code for all things demonic.

There are significant contigents of High Elves in the Hinterlands, Loch Modan, Stormwind, and Theramore (at least as far as storyline goes, most Alliance-loyal high elves live in Theramore, they fled with Jaina instead of sticking around with Kael'thas Fancypants)

There is a High Elven faction in Wrath, The Silver Covenant, which is the Alliance-only Dalaran faction, they're militantly opposed to the Blood Elves and the rest of the Horde for that matter being allowed into Dalaran and the Kirin Tor at any level. Their leader is Veressa Windrunner, Sylvanas' elder sister (Alleria Windrunner is the eldest and alive, somewhere, with Turalyon).

Vereesa is a sucky ass character. I hope her big sister, Sylvanas, eats her brains.

Oh and please, these High Elves who remained Blood Elevs were citizens of other nations, so they don't know the hardship the Quel'Thalas High Elves (that became Blood Elves) have gone through.

Also some numbnuts from Theramore attacked a High Elven ship thinking they were Blood Elves hence why there's two High Elves near Ratchet that gives quests to Horde players.

I think the point is, there are two distinct variants of highborne elves at this point, three if you count the Naga.

High Elves do not feed on other beings' magical energies to sate their addiction. They meditate or seek aid from the Night Elves, whose moonwells can "cure" them so long as they stay nearby.

Blood Elves use trapped demonic souls to power various magical constructs, will suck the essence out of anything to get a magical fix, and a few of them will absorb demon's blood because they're total crackelves at this point. At the beginning of BC, and it has been seen since, they have operated their city as something of a police state, evident from the minute you go through the gates. Demons hidden away in closets, gnomes in cages, more and more green glowing demon-crystals, brainwashing of the populace. That may be changing, though, with leadership entirely in the hands of the not-insane Lor'themar Theron, however.

So my point was that High elf != Blood Elf, to the guy who said it "went against the lore".