JSW, that wasn't even close to my toes.

Just in case this wasn't known , there's a
huge difference between a mod made by volunteers that is available for free (like the StarGate mod in consideration) and an actual commercial game that is sold to make money. As soon as you start getting compensated for selling someone else's idea, then you're essentially piggybacking on that company's business and stealing their potential revenues.
Many companies don't really care too much about whether people use their intellectual property for other reasons, although some will close you down quickly - Blizzard (who recently canned a free version of StarCraft) and Games Workshop (who are fiercely protective of their intellectual property) are two examples. We actually asked David Weber if we could make a Homeworld 2 mod around the Honor Harrington universe and were nicely told no.
Usually, mods are small enough projects that it's not worth the bother for the IP-owning company to ask the people making them to stop (which is why you'll see Babylon 5 games offered). But SELLING that game is an absolute no-no. IronClad would very likely be sued if they were to make a StarGate game without paying licensing fees to the company that owns the show's rights.
Regardless, people won't buy a game that has nothing in common with its branded series except a few ship models. Trying to rationalize StarGate's plot in the Sins gaming model and sell it for forty bucks would frankly be ridiculous.
-- Retro