Live is now free so it isn't a reason anymore, although they did try charge from online gaming.
But there is also an issue of license fees. PC (and Mac) doesn't have license fees which is one reason why games are cheaper on PC. WoW has made huge profits but MS doesn't get any money from sales of WoW. And neither from Sims, Starcraft, Diablo etc. Only PC games which gives MS profits directly are published by MS. MS only gets money by selling development tools and indirectly through selling Windows. But there are many development tools from other companies (even open-source tools) too so you don't have to use them either.







