i know that, but ive seem on older panthers having the elastic bottoms.
over time, the springs ans wires break, at least thats what happened on my 03 marquis and 08 f450. and im only 200lbs lol
And that is why you buy new springs, install new wires, new high-density foam, and stretch a heavy canvas membrane over the wire hammock.
Good upholstery mechanics know all this. Had it done on my Marauder (see link above). It was a huge improvement, but it cost more than $8.