That's kind of retarted. What if the goal is 5,000 dollars and you end up with a thousand backers? How will you fulfill that?
That said, none of the crowdfunding sites offer any protection against scams. And I'm not even talking about CG situations. There have been multiple examples of Kickstarter campaign creators running off with the money a month after the campaign ended. Kickstarter's response is essentially "shit happens".
In the case of Karl O'Rowe, who posted that he only had the cover of the book left to finish and then disappeared for a year, IGG just took his campaign offline until he came back, since it was still InDemand.