ap set, they randomly pick a box for it. that is why.

the ap distributors get those sets in bulk, and then open all of them, check for their condition, put on stickers etc and then simply take the box of same model and sell off to the shops.

or the storekeepers take the sets out from the box to be put on display and simply take a box of same model, when the display set is sold.

but for ori set, the store keeper will not take the sets out from the box.

so sometime you might get a box of same imei as the phone, but rarely.