Because Microsoft wants to lock in developers to their expensive OS so they can make billions more, obviously. It's because programmers are expected to not be the smartest bunch and just be shoveled around with a bit of money and marketing expenditure. You know we took all the free stuff and made it proprietary, come serve are corporate goals. Meanwhile they have been allegedly screwing over Linux for years with backend deals with companies like Foxconn.

http://ubuntuforums.org/showthread.php?t=869249