After watching some guys at a LAN trying to get it to work without having to buy it over Impulse, I figured it out. I know what they did. I know why they aren't on Steam right now, and I know why they will consider it down the road.
They let the DEMO hit Bittorrent. 
Yeah, it's a freaking demo. It's 100% of the game, but with limited functionality. You can play single player all you want, but multiplayer requires that you log into Impulse and download an update. The update doesn't exist as a standalone installer outside of Impulse, and you can't update the game without paying for it.
Yes, I would rather have this game in Steam so that I don't have to launch a seperate app just to lauch this one game, but I will applaud them for a brilliant idea. All of the news outlets thought for sure the 180,000 illegal copies were a sign of how screwed Stardock and Impulse were, but they were all 100% wrong.
Until someone makes a crack that allows multiplayer without Impulse, they have no reason to worry. Let those 180,000 users face reality. If they like the game enough to play it with friends, they can pay for it. If they just want to mess around with it at home, they can. And no one at Stardock will say a word to them. Then a few months from now when the pirating has slowed, they can put it on Steam and sell more copies.