Maighstir: As the current owner sees that "hey this old thing we own is still popular enough to earn us money" they might start to think "perhaps we'd get more money if we pay someone to make something new that relates to this old thing".
F4LL0UT: Keep in mind, though, that publishers use the revenue of one project to fund another, so in a way at least part of your money ends up with the creative guys, just not necessarily the ones who specifically made the game you just bought.
Wishbone: By buying it, you're still sending the signal that whatever money they spent so they could sell that game was a good investment.
Guys, we're talking different things here. It goes without saying that demand creates it's own supply. But initially this topic was not about stimulating development of specific kinds of games. It was about rewarding specific people for their amazing creations. And in the current state of affairs it is only possible if publisher decides to re-hire the same team of developers to do a sequel or whatever based on good sale numbers of their previous project.
Darvin: There is the unfortunate irony that consumers can't directly support the creators, but the system in itself is not the issue. The problems emerge from the fact that the negotiating table is stacked heavily in favor of those with deep pockets.
Very few people can afford to go for years without a salary, which means walking away from a bad deal isn't always an option. Similarly, if you end up in a dispute with your investor you'll need a massive legal budget and the financial stability to weather potentially years of litigation to take on a powerful corporation in court. Even a slam-dunk case can be difficult to win. Creative people also tend to be intensely focused on their creative passions; when it comes to business deals they're out of their element and easily outmaneuvered by lawyers and other professionals that specialize in that kind of stuff. That's why creators are often left holding the short end of the stick.
Umm, please remind me, exactly how is "the system in itself not the issue" here? Everything that you mentioned are the traits of the system and I will even add two of the more fundamental ones.
First: We're dealing with information here. Information, which is not physical and cannot be treated as such in terms of economy. How should it be treated then? Short answer - nobody knows. Currently, there is no generally accepted view on this matter, even in theory.
And second: The rise of digital distribution reduces the publisher's involvement down to investing money into developer's work and then living off of it indefinitely. Where formerly there were problems of data medium creation and logistics, which justified publisher's presence in a "manufacturer to customer" relationship, now there is just an occasional lawsuit against copyright infringers. Which is why a lot of smaller developer teams opt to monetize their games on their own using such initiatives as Humble Indie Bundle and Steam Greenlight for promotion.