I don't really know, but it could have something to do with my lousy sense of smell. I find chocolate (aside from not caring much for the taste) to be a little too rich and intense. My sense of smell is awful -- I'm not used to smelling things very strongly and if/when I do, it can briefly nauseate me -- even pleasant smells. The only smells I can easily identify are cigarettes and skunks.
We weren't married very long when one evening Mr.FF came home and immediately got panicked that one of the gas pilot lights went out on the stove, and I hadn't smelled it. He lit it and ran around opening windows, all the while yelling that I could have been killed! All I could say was "how can I know if I don't SMELL it?!"
Oh that's interesting FF! That explains a lot I think since our sense of taste is tied up with our sense of smell. Probably don't like perfume either.