I totally agree that, if you can't think of why you might want to support one particular future game over another, then kickstarter is not for you. However, lots of people like the work of particular creators, or like particular genres, or are looking for particular gameplay approaches. Those people may all think about funding certain games in development over others.
Just in general you might prefer to support some futures over others, and if that's your, kickstarter (and similar services) would appeal.
