Oh I don't know. You guys are very good at saving money on video games, which already puts you in a different state of mind than people who just want to play them.
From that perspective, it doesn't matter how much you are theoretically saving if you are never going to want to play the game. In this case it makes more sense to save $8 on something you will play than to save $15 on something you will not.
Edit: I do sympathize though. I also play games on my PC, and could get Grow Home even cheaper from there, while Armello isn't even available yet (as far as I can tell).
Armello's been out on Steam for a while as an Early Access title. With the launch coming in a few days, they've pulled it so they can have a proper launch for the 1.0 release.