Maybe I'm paranoid, but I think that is someone posting someone else's pigs, like an exboyfriend or roommate. The guinea pigs show so much care, but she's dumping them for free and not caring if they're separated or not. And she could easily downgrade the cage if space were really the issue. Plus saying that newspaper is fine as bedding--anyone who knows about guinea pigs (and someone with that cage knows about guinea pigs) and cares about them would never say that.
Here's a two year old abby boar on an urgent rehome, owner moves Saturday for Sweden, the home he was supposed to go to fell through. Brooklyn, NY:
The cutest guinea pig is urgently seeking a home!