TV and news agencies sell controversial stuff, indeed; moreover, negative news sell better than positive ones as I know.
But I guess that Reddit prefers promoting posts with maximum upvotes. So if you want to appeal to Reddit readers' emotions, it's probably better to be with them against their enemy (sharing posts about homophobia in gay communities, for example).
Oh yes, not negative stuff, things "neutral", like "should pizza with ananas be banned forever or not?"... It's not a yes or no, some people will side for yes, some for no, lot of arguments hence views... Still not negative topic