Headline says “without opening the boxes”. So does the article:

Crucially, it can do so without opening the box.

Consisting of a "pad-like device," store employees place unopened iPhone boxes onto it to trigger an update.

Unless you meant taking out every unopened box, in which case, they probably have some half streamlined system in mind where employees can cycle the boxes in seconds. Would be interested to see the plan too honestly

Perhaps updating a set number a day so they can take phones off the pad right before selling them, or for less used models, updating it in the back while talking to the customer?