Traditional scales are designed to change the leverage as the pans go from even. Also, it's a 1 kg mass, not a weight; weight is a force proportional to acceleration.
In any case holding the item against the fall from gravity is accelerating the item.
There are several demos on YouTube of accelerometers being wired to speakers to make a noise proportional to the acceleration. They all go silent when dropped, indicating they are not accelerating in their own frame of reference when in free fall.