Mmm...I don't think I agree with this. If a quest reward was that I was taught how to do something cool (basically a free feat? are feats magical?) I'd find it equally satisfying.As long as it's some /magical/ ability, sure.
Classic D&D had many examples of arbitrary abilities granted by interacting with the environment ("I drink from the glowing pool!") or getting a whammy put on you by some uber-being (god or devil or high-level wizard or whatever) for good, ill, or some combination.