Holy crap! You might be right. I don't know why I've never considered that. Actually, yes I do. I didn't even know it was possible to make a homemade suppressor with a cardboard box at home. But apparently, not only can you make one, but those plastic wrap boxes are ideal to use because of the holes on each end of the box.
(I'm fairly certain that my search history has landed me on an FBI watch list somewhere.)
I dare not look, but can someone really make a silencer from a cardboard box? It may not be of any value in this case, but it would be interesting to know.