You're not purchasing anything on Kickstarter though, you're making a donation.
When you pledge to a kickstarter, they're committing to providing the rewards stated for the money provided.
The difference between that and a standard purchase is that the product generally doesn't exist yet, which is why there is a risks section attached to every campaign, so that backers are aware that the product could run into problems.
However it's not a donation.
This one is probably on older Kickstarter T&Cs so it'd be harder to get money back. In more recent times Kickstarter have tried to toughen up a little after early failures like ZioneyeZ
The difference is that you're usually not expecting anything physical in return.