Junkie, I am in the same boat as you. I am 6'5" and 210lbs and I burn air like crazy. I am in great shape, but even sitting and watching TV, I breath fast and deep, so I chalk my problem up to genetics. But I have stopped worrying about it because I found myself thinking so much about breathing that I didn't really enjoy what was around me. After I stopped thinking about it it got a little better. One other thing that helped was I got a ScubaPro regulator with the air flow adjustment. I just cranked it all the way down to minimum, and although I still breath alot of air, it actually did help my consumption a bit.
Just don't try to change the way you are built, rather embrace it, accept that you use more than others, and enjoy the time you are down.