Comment by RandomGerm4n

Only a very small percentage of players purchase microtransactions. In addition Turtle doesn't have any payment information because the transaction went through a third-party service. So Blizzard would have to take legal action against that service first. Also the server itself is not “piracy.” The server is based on VMaNGOS which is open source and contains no Blizzard code. VMaNGOS can be downloaded legally from GitHub. Turtle WoW created its own content for the server some of which runs on the server side and some on the client side. The only thing that is actually "piracy" is the distribution of the game client (which they unfortunately did) as it belongs to Blizzard.