That's absolutely disgraceful that they've done that. Without the kickstarter backers, they would've had a hard time getting it published, if at all. They should be rewarding the people who got them to this stage, not shafting them...
Out of principal, due to their shady business model, I will avoid buying this game. Would be nice if others did the same and boycotted this title. Would teach companies like this a lesson regarding fucking their fans about.