I have had this happen to me as well. However, it did seem to happen to simple lines too. But it's inconsistent. I just tried to replicate this and it went fine without the weird approximations, whether the shape had a stroke or not.
One thing I did do that is different is if I want a shape with a stroke, I first set the stroke to zero, remove the stroke paint, resize it, and then apply the stroke paint and stroke width. When I resized it, there was no strange approximations.
I have had this happen to me as well. However, it did seem to happen to simple lines too. But it's inconsistent. I just tried to replicate this and it went fine without the weird approximations, whether the shape had a stroke or not.
One thing I did do that is different is if I want a shape with a stroke, I first set the stroke to zero, remove the stroke paint, resize it, and then apply the stroke paint and stroke width. When I resized it, there was no strange approximations.