matt,
You can flip over doing a wheely and kill yourself.
Once you start, you won't stop.
Other, more "mature" motorcyclists will consider you a plague to motorcycling at large, corroding the image of good motorcyclists with those bent on wheelying at will.
Furthermore, depending on where you live, a wheely is considered "reckless driving", and you will get a misdemeanor infraction, get booked, and see a real judge... not traffic court. But don't ask me how I know.
I will give you a small piece of advice. When accelerating hard in first gear, practice keeping your foot over the rear brake. In the midst of hard acceleration, see if you can "tap" the rear brake. You'd think with all of a motorcyclists coordination that "tapping" the rear brake while acceleration hard would be simple. Give it a try.