Because it is contrary to the stated purpose of kickstarter. I am treating the backers like adults. Why do you think that "hey, that's really not what kickstarter is for" is patronizing?
Where exactly is that stated? As far as I know, and according to the FAQ and project guidelines of Kickstarter, there's no rule or implicit understanding that only creators who can't fund their own projects should apply. In fact, they specifically mention that KS is about more than money.
And I find it patronizing because your complaint is about the poor backers who get nothing for their money. Why exactly do you feel qualified to judge that on their behalf? It's up to them to know what they get in return, and if that should or not be important in their decision to back the project.
That wasn't papsosouid's complaint, which pertained to the fact that the project creator can afford to pay for the project, and so shouldn't be using KS.
You say it is contrary to the stated purpose of Kickstarter. Can you link or quote something to back that up? All I've ever seen them say is that it is a platform to fund creative projects. This is a creative project.
For game developers, even millionaire game developers, Kickstarter offers some level of freedom from real big bilion dollar game publishing corporations. So even if Richard Gariott has a lot of money, maybe you can at least appreciate he is a little guy in the context of the game publishing business.
The same reason blatant scams get allowed, kickstarted has a significant financial incentive to allow as much as possible. Why would they shut down a kickstarter that will put $50,000 in their pockets?
How does that possibly fit with your claim that it is against the stated purpose of Kickstarter? Kickstarter gets to define what their purpose is, and their actions are as clear as their words. You'd have stronger ground complaining about Kickstater than this project.