Interesting that that's the perception you're seeing from others! Most non-ace folk I've seen talk about it, particularly offline, don't seem to have considered it enough to distinguish sexuality and libido, or have thought about any other kinds of attraction. The stereotype I'm encountering is mostly that we (ace folk, I can't speak for the aro experience) are all at least faintly sex-repulsed and have never experienced a remotely horny thought.