When you make a copy of a circle, makes the copy larger, and then center both, the edges of the copied circle will always be of equal distance to the original circle.
With complex shapes however, this will not be the case.
I’d like to see a feature where this could be achieved.
The reason is:
I tried to make a gradient on the stroke of a shape, and I don’t think that is possible?
So I made a copy of the shape, applied a gradient, and put it behind the original shape to give the impression of a stroke.
But as mentioned above, the distance between edges of the original and the copy varies, the less symmetry, the more it varies.