This game does give me the heebee jeebees. I don't know if it deserves to be removed from the omnipotent Steam's glorious marketplace because I haven't played it but man is it a disgusting looking game. It embodies evil. I assume that was the intent judging by the name.
That's a huuuuuuuuuge market to disappear for the developers so this probably hurts them a lot. At the same time, this game probably benefits a bit from controversy like this. Now the people that want to buy it are going to look that much harder for it and the potency of their experience will be even greater. The coverage of this game all thrives on people making a bigger deal about it than it is. It not being available on Steam gives it credibility.
I have a feeling the developer knew full well it wasn't going to get published by Valve. It fits too well with other AO games that have been rejected in the past. But putting it out there like this garners them some extra hype and coverage. They may seem out of touch in some ways, but they also seem to understand the current subsection of bitter gamers that will likely support them no matter what. They can capitalize off that anger and potentially make a good buck.
As an artist, I personally support them being able to make whatever ridiculous thing they want to make, but I also support Valve's decision to not string them along in the Greenlight process, as they were never going to publish them.