Not at all. "THE GAME" is on the cartridge so of course you don't have to download it, that statement was unnecessary we already knew that, otherwise there wouldn't be anything on the cartridge. However their statement doesn't rule out in the slightest that a big 13GB whopping download will be required after you boot "THE GAME" that's on the cartridge to be able to play the full extent of the game. Sure the download may be free, but still, on a system where storage is either very limited or doesn't come cheap at all, it is a very important factor in a purchase decision. If you don't plan to have any massive retail downloads so as to not have to juggle with multiple micro SD cards (and not have to pay 50 bucks per large card either) then it makes a BIG difference, and who's to say that they're not avoiding to be perfectly clear about what's written on the box so that people who would otherwise not buy the game for the aforementioned reason would still dive in anyway, only to have a bad surprise afterwards?

Because they won't say so outright, most people will wait for poor souls to take the plunge first and tell them how the water is before they make their final decision.

EDIT: Well now they've come out and spoken again to IGN, so that's cleared up now, that the info on the box is wrong.