It's no scam. The guy probably decided since the game had done so well, it didn't need his 10k to be made.
Sorry but if you are right that kind of thinking and behaviour is disingenuous and is unacceptable for a system like KS. It should be unequivocally condemned
If a person bothers to understand how the structure of KS works they would know that it is this kind of action that can effectively destroy the hopes of thousands of fans and lead to huge disappointment for the developers or creators of the particular KS. This is not a game for some people but there livelihood and aspirations.
Also I'm not talking about changing a relatively small pledge like $100 but a person who commits $10 k knows if they can afford and is serious about it. You can't change a pledge of that much unless you weren't serious about it in the first place