Those also are quick unfold and they are assembled. They make laundry baskets, dog kennels, kid tents, all sorts of things like this.
I don't imagine that would keep your pig out, I know my bosun with have it figured out in a matter of seconds how to knock it over.
Most playpens aren't that sturdy. That is why they either need modifications or just built from scratch.
What size cage are you going to be using?