At E3 2011, Microsoft made it painfully evident that they were going to try and sell Kinect to the “hardcore” crowd. How would they do this? By integrating Kinect support wherever they could while not altering the core experience. This probably meant Kinect support would be added to games just for the heck of it offering nothing significant in the process. We saw it being done in Mass Effect 3, Forza 4 and now Halo Anniversary, the HD remake of Halo combat Evolved is next in line.
Master Chief doesn't need Kinect
Kinect support for Halo: Combat Evolved Anniversary was confirmed by a Microsoft spokesperson to IGN who said “The Kinect features we're exploring with 'Halo: Anniversary' are additive and will not affect the core gameplay experience or alter our mission of delivering a faithful recreation of the original game. That said we have nothing else to share just yet.”