im sorry maybe i was unclear: they get to keep their servers and their, in my honest opinion, AWESOME way of making games and telling stories, however, with releasing the bits that made all that awesomeness, free creators could make content to give away for free (because the joy of creating is reward itself) back to blizzard and they get to choose what they put in it. Themselves say they wish they had more content to put in and people are standing outside the wall with tons of ideas they'd love to share. Look at the UI again, it was released free and people have been developing it for years eventually leading to products that made it into the game.
What do they gain by holding on to marketshares and stuff, it was the playhouse for the children that made that market possible to begin with??
sorry i seem to have lost my concentration, luckily my government is working on building a camp for people like me