All those games already have their own in-game currencies... They don't need a blockchain based cryptocurrency. Runescape has gold, World of Warcraft has gold, League of Legends has gold, etc. They all have individual in-game currencies. There's no point for them to use a blockchain cryptocurrency since they would need centralized control(Its just games guys).
Exactly. That was my point. Firstly they don't need another currency, secondly they can create their own. They usually have an in-game currency and lots of different tokens.
So it would be surprising if Blizzard became one of the earlier adopters.
I doubt that too. Leading companies like Blizzard or Valve are usually looking at revolutions with some distance. They will be watching and if some other smaller companies will adapt bitcoin and it will go nice for them. Then probably Blizzard in anticipation of increased income will adapt bitcoin overnight.