What does it take to get sent away for a Ponzi scheme? Isn't that when you say "we are doing XYZ with your money" but really you aren't...?
Sadly, I don't think Kickstarter has any kind of legal expectations or promise when you hand over money. It isn't as if these people were buying a share in something.
It's like suing a homeless person when they buy beer with the money you gave them even though their sign specifically said they wouldn't.
Stories like this just make me really think about all sorts of Kickstarter scams I could start.