If you check out Fantasy Lingerie's site, they offer those in "one size fits most" too, which I'd guess are the ones being modeled.
I think we get kind of spoiled by awesome companies like Coquette and DreamGirl that are helpful enough to supply 2 different photos for post items. Think about regular clothing- flipping through the pages of any fashion catalog or website, you almost never see two different photos for the straight and plus sized versions of an item.