There are two issues here, and I believe you have comingled them.
1) legality with respect to sales tax law: If Kickstarter actually requires that a good is shipped when money is given (the statement I was responding to with this comment), then this difference is barely even academic: it is just a way to do an end run around sales tax law, and I don't think it is one that most places would tolerate well (although enforcement on that sort of thing is slow and spotty).
2) terms of service on credit cards regarding pre-ordering: No, if you are giving Gamestop $60 to hold on to until a product is shipped, and you do this with a credit card, this is in violation of their agreements with companies like Visa. These requirements (obviously) flow through if you use third-party payment networks that, themselves, are based on the usage of credit cards by the end customer.
In fact, this is sufficiently true, that your example is actually wrong to begin with... Gamestop doesn't even do that, because (as I said) if they did they would be in violation. They have a page in the help section of their website where they go over this topic in specific.
http://www.gamestop.com/gs/help/Pre-orders.aspx
"""Your credit card will be charged only when your order is processed. In some cases, we will process your order and authorize your credit card up to 10 days before the release of the product. This allows us to get the product to you faster."""
In essence, they are taking your credit card number ahead of time, but they are not actually billing you; it is only when the product is actually pretty much available that they do the authorization on the card. Even then, I bet they are doing only an "authorization", and performing the "capture" when they ship: they do the authorization ahead of time to make certain there is time to deal with delays, mistakes, or simply a long queue, and then can do the capture quickly when they go to ship.