Apparently it's for visibility as I've been told. So if you have lots of money then your comment is more important. So you upvote it to the top of the list so everyone can see it. It doesn't even matter if the rest of the blockchain thinks it's a good comment it "Deserves" to be read.
That's what I've been told
"Just for visibility" is again, something that bigger self-voters mentioned now and than, why did they do that, and continued with the comment due to the article. What you have been told is pretty accurate :) And I 'd also upvote your comment but I delegated most of my SP, so my upvote is not worth even a cent