When I exchange my note 7 for the new one, I'm going to leave my old stuff at home hoping to gain an extra charger out of the deal. It's hit and miss with rep asking for the accessories that came with the phone, if they do then just tell them to take the ones that came with the new phone, they will do that, I've done that before. Sometimes you get lucky and gain an extra charger. At the very least have it on your car just in case, but might as well try.
Obviously if you choose to return the note 7 for a refund or exchange it for the s7 deal then obviously you need to return everything.