What people don't understand is

Atnol, in Blizzard’s post they specifically said “automated” gameplay.

And it’s hard to say that Blizzard thinks boosting or “EXTREME cases of gold farming” fits into the exploitative part, because boosting has always been allowed in every iteration of the game. It has almost never been punished, unless Real-world currency was exchanged. Also, people would need to be gold farming, like you said, in extreme amounts to have a significant effect on the economy.