Good point! Supply and demand only works where there is no competition among producers. In a competitive market, selling above production price wouldn't work for long.
Can't tell if you are messing around or what here.
Supply and demand works with competitive markets, but it also works in an absence of direct competitors where a good is not required.
For instance, if Goko put their prices at $20 an expansion, a few people with lots of extra spending money would bite, but the majority would not. That creates a low demand situation, and the result is that not enough people would buy the expansions to cover Goko's operating costs, so they would lower their prices. The lower prices match consumer's expectations much more than previously, and the demand for an electronic Dominion implementation matches the price point enough to increase the amount of people willing to buy to a point where Goko can sustain itself.
Just because no one else has the license doesn't mean we are all forced to buy at a $20/expansion price point though. That's silly (or maybe it's some odd extension of communism where because Goko needs money we are forced to buy their service to help the economy or something).
If you were just messing around, man, good job, because you confused the pi55 outta me.