I was going to writ a post about this as the have been downvoting all of the comments on my posts too, and I never downvoted otheir follower comments - although I did downvote a few of theirs as I was testing the effect on reputation. However, they were already greyed out for the most part and it took nothing from them.

I figure they are trying to "scare people away" from commenting on our posts for some reason. So far, I have been healing what I can because even though I know that most of the people who comment understand the game, some don't. However, I am considering just leaving them greyed out instead to show what these kinds of people are like. Pretty piss poor and pathetic behavior, but then - this is steem :)