I agree with you. Upvoting one's own comment and not upvoting the post they replied to seems odd....maybe selfish? Or maybe the person didn't like the post but liked their own comment in response to it? Or, maybe they thought they already upvoted the post? I don't know.

Personally, I hate playing games with upvoting. If I happen to be on Steemit and read something that I like, then I want to upvote it and usually reply to it. I don't want to hold back because I'm worried about losing voting power. I understand that some people abuse voting and that is why the "rules" are in place.