A lot of the excess goes into producing the fancy packages they send out to the bigger donators.
They also said it will mean they can expand the business, as it is its just the two guys who run the card company who do all the work at the moment. They said they will hire an assistant, and that it will give them an opportunity to get ahead on future projects without having to resort to using Kickstarter to fund all off it. They are very open in all the blog posts and updates about where the money is going.