selling devices to minors using other customers informationmed

my little brother stole my mothers bank card and purchased a device at pep jane furse yesterday of which we don't blame the store but my concern is how was it possible to sell a smart phone to a minor with no id or proof of reside.My Mom went to the store to return the the device as she need that money.And where is it written that the devices cannot be returned.Im so disappointed because the slip is there,And the device is still on its original packaging