You have not done your homework properly. What I see is that those posts were from very early days of introducing the merit system. That time most of the people did not understand very well before they send merit to each others. I was not there that time however this is a guess using commonsense.

Merit does have a use to appreciate good quality posts, it's not just linked to ranking up. A good quality post does not have to be a very long and highly constructive. A single line comment could be a good post depending on the humor expressed on the comment.