For ‘tactical advantage.’
The new update for Metal Gear Solid V: The Phantom Pain may have brought with it Metal Gear Online (at least for the console versions of the game), but that is not all- apparently, it also brought with it the previously announced costume DLC, that can be used for either Snake, female soldiers, or D-Horse. These are now available to purchase on the Xbox Live Store, and cost $0.99USD / €0,99 / £0,79 each.
The costume DLC is not strictly cosmetic- it appears as though several kinds of tactical advantages, from retaining body heat to better camouflage, are afforded by these costumes. I am not sure how I feel about this kind of content being sold piecemeal as DLC, but of course, this is Konami, so I am not sure why I expected much better either.
Metal Gear Solid V: The Phantom Pain is out now on PS3, PS4, Xbox 360, Xbox One, and PC.