The covers do get hogringed to the springs although indirectly.
The soft trim of a seat is a build up of layers of different materials
fastened to the steel frame & springs.
The factory used a layer of burlap reinforced with wire as a first layer.
This is to spread out the load across the springs.
Also to prevent springs from separating and allowing foam and cotton to be pushed thru
becoming unsupportive.
Next a paper wrapped wire is attached. This is what your listings will anchor to.