Well shit, I mean, would it kill Nintendo to ship their products fully charged.
Why yes, yes it would. Hardware and device manufacturers do that for a very specific reason, not to piss off consumers but to prolong the battery life. Most devices sit in a warehouse, in the backroom of a store in a stock pile until needed or on a stores shelves for expanded periods of time. So even if the device is not in use, the batteries will still slowly lose their maximum storage capacity due to age, the surrounding temperature and so on.
QUOTEThe capacity loss begins from the time the battery was manufactured, and occurs even when the battery is unused. Different storage temperatures produce different loss results: 6% loss at 0 °C (32 °F), 20% at 25 °C (77 °F), and 35% at 40 °C (104 °F). When stored at 40% - 60% charge level, these figures are reduced to 2%, 4%, 15% at 0, 25 and 40 degrees Celsius respectively.