I think you hit the nail on the head.

As long as people can vote themselves an ROI, they will. I see so many not only upvote their own articles, which makes some sense, but every comment they make. What is funny is when someone comments on the article with something positive, doesnt vote the article, but upvotes his comment. I had that happen to me today.

I think you are onto something with the Influence.

Although at the end of the day, most people will act in their own self interest.