I also want to know what they pay to WOW TBC Gold keep the servers running, the development of tools to manage all of this, the development of tbc in this version, the teams that have to maintain everything and so on.
Everybody claims that this is free and Blizzard is making us pay. In reality, nothing is free.
Take it in this manner. You had a support staff that supported whatever is the most modern version of wow. You could then add traditional. It's unlikely to buy WOW Burning Crusade Classic Gold increase the amount of work, but it is an enormous amount of new content to maintain. We're now adding tbc...again to increase the support team for teams that require it.