I think Innie vs. Outie is basically a question of how much fat/muscle surrounds the navel. In westerners, I've only ever seen close-to-Outies on (pictures of) long-term followers of low-weight/high-reps exercise programs (e.g. aerobics instructors, long-distance runners) -- or people with debilitating illnesses (e.g. cancer patients, anorexics). The former is just about OK, the latter is obviously unhealthy/unattractive.
Conversely, the only place I've seen majority Outies in any population, is photos of famine-struck kids: bodies stick-thin, but bellies (comparatively?) bulging and navels everted. Given how much food we produce (and waste) yearly, famines would be 100% avoidable, if we (humans in general, rich western nations in particular) cared more about each other than we do about personal profit. In that resepct, yeah, for me Outies are gross, because they're generally a symptom of inequality.