If you (one) actually wanted to see the game made, were not concerned with money/power, and lacked the time or expertise to create it themselves, one (you) might submit their idea to a popular game developer in the hopes of it being used.
The chances of this (ie the game making it to the pre-development stage, at the least) are astronomically low, of course, and the chances are slim that Stardock would hire that person.
Of course, if that same person thoughtfully and carefully laid out a full game idea that they spent many hours/days/weeks perfecting, and attached it to a carefully filled out resume for a
Game Developer or Senior Game Developer [link="https://www.stardock.com/jobs.asp"]https://www.stardock.com/jobs.asp">Link, they might have a chance, but otherwise is extremely unlikely.
It would be better to apply for a job at Stardock directly than to post complicated, redundant game ideas and hope they get picked up, though (try an open-source engine or game forum, perhaps), because Stardock only has one (1) full team of game developers right now. Their current projects are enough to keep them busy for a while - they will be working on Dark Avatar quite soon, if they aren't already, for its fall release. Then they have at least two (2) more projects in the immediate horizion beyond that: Society and a fantasy TBSG (turn-based-strategy game). More expansion pack plans for Galactic Civilizations are also in the works; GalCiv III is inevitable. I would say that the chances for them developing a user-suggested game will be quite small, but the opportunities for being hired are relatively good, provided you are a competant game designer and not a bored teenage gamer.
Edit - Stardock get there before me

I doubt many would post a game idea on Stardock's forum and then hope to get paid for it, though