[zanny]

There are hundreds of private servers out there. I know of at least six that are near-perfect recreations of vanilla, BC, wrath, and even cata. If the main game died, these private servers would continue to exist. Most of them are actually self-funded and self-sufficient as is. I played expensively on a Cataclysm private server, because I had quit in the first patch due to brokeness and never had a chance to actually see Deathwing (in its intended form at level 85) because Pandas had come out by then.

In reality, the game has gone away. Every time a new expansion has come out and reset everything millions of people had their old game taken and were given a new game. And sometimes, they didn't like the new one, and sought the old one. And even if it is illegal, the market is providing their demands. There are even a few open source projects for server cores to run WoW on.