It is a well-known phenomenon that people prefer to put their money where lots of other money already is. It feels like a safe investment. And, as you note, people aren't only enthusiastic about positive notes. They're also enthusiastic about insightful, uncanny, or revelatory notes, which are often "negative" in tone. That isn't reflected in zap statistics because the follower count is by far the strongest pull-factor, as visibility is required to receive a zap. We would have to analyze zaps/views, in order to determine a correlation.