HD is completely a different dilemma to compare to Voobly. First off there's the steam client that consumes data nonstop and lots of it if you have many friends and don't forget the steamcloud it's between 1 - 60 mb or more before any game starts. Steamclient does some asynchronous downloading and updating in the background. So yeah It makes sense for all that data to be consumed. To economize consumption you'll have to login in offline mode which disables chat client, disable steamcloud, and close steam windows.Cple years ago I played a few dozen games over 4G hotspot on HD Edition and in my experience it consumed a bit more than that in practice, about a couple MB for 1v1 and afair up to 50+ MB for longer 4v4s. Then again that might have to do with the HD edition (maybe it consumes more data)
Also: for some reason i couldnt play via 4G Hotspot on voobly at all (fast proxy to everyone)..