To be fair to the team, Tor (from PirateSoftware fame) reported that Blizzard made more money selling one horse in WoW than with the entire Wing of Liberty:
Well, the horse costs only 4x less than the game. WoW has an insanely larger market cap.
It's not crazy that people bought the horse in more $ amounts than SC2's first release. It's crazy that people spent $15 on a single cosmetic.
I don't fully trust piratesoftware guy, since he does do a lot of clickbait, and isn't exactly a well known body from Blizzard. But I do reckon that micro transactions for a larger game would well outsell an old purchase model on a smaller game.
And yeah. We can only blame gamers for the way video games are now. The good games rarely get acknowledged, but the bad games proliferate continuously.
https://www.youtube.com/watch?v=IHZru-6M8BY
That would screw up anybody's motivation a bit.
Players get what they incentivize, and thanks to video games getting more and more popular, the tragedy of the commons applies.
Still, it sucks.