I think it comes from my aversion to "mixing" certain foods, but I don't care for omlets - I like my scrambled eggs, but I like them plain. I love a lot of the add-ins people in this thread prefer, but do I want them in my eggs? Not so much. I may eat it on the side, but can't have it mixed into the eggs.

I also hate cheese (the smell of it actually causes me to be nauseous), so that could be another reason I've never been "into" omlets.