boomernickel, if you're new to skiing, you should not be trying to "go straight and carry a lot of speed" on Super-G skis in public. That is a recipe for killing yourself, or worse yet, killing somebody else. You parents bought you slalom skis for a reason.
Besides, anything can go straight and carry a lot of speed. If you strap a rock to some skis, it'll go fast and carry a lot of speed. An out-of-control beginner goes straight and carries a lot of speed (before he/she crashes). If you jump off a cliff with your skis, you will go straight and carry a lot of speed (before you die).
The whole point is to develop the strength and technique to turn and control your speed and direction. To develop the strength necessary to maintain stability when your skis seem out of control. They're not really out of control; it's simply that you have not yet learned how to control them.
(Ghost, might want to check the OP's profile and post history.)