I am on some auto-vote lists. There are also some people who upvote the "Reports from the Witnesses" post because of the value it adds to the community, even though they may not read it themselves. There are also people viewing posts through busy.com and other interfaces that don't show up on the Steemit.com view counter. Also, there are voting trails - where one user votes, and many other people automatically upvote based on that person's evaluation.