There's only 1 reason to self vote a post/comment.
To get visibility and bump up the list.
Steem is built with Proof-of-Brain consensus algorithm where rewards are determined by crowd wisdom. What's the value of the Steem Blockchain when one can vote themselves to get more steem?
It'll be akin using 1 dollar to buy 2 dollars without offering any form of value to justify that returns. What is the value of the money then?
In my opinion Linear Reward was a mistake.. No doubt it's the most "profitable" but it is hurting the ecosystem. The biggest industry on the Steem Blockchain isnt in creating good content that gets accepted anywhere else but is in the abuse of the reward pool.
I agree with @kevinwong's stand a few weeks back that a Superlinear Reward curve is necessary to create a form is diminished returns when a post gets too much undue attention by way of self-votes and vote-buyings.
Otherwise we are destroying the very thing that gives the Steem Blockchain any value.