I still want to know what experiment the rat left in an aquarium full of water was supposed to be accomplishing beyond pointing out that Stephen Root was evil. He says drowning is a great motivator, but there was nothing for the rat to do, but swim until it drowned.
As to Casablanca references, I'm curious if other George Romero movies make a lot of them. I can't recall any off the top of my head, but I wouldn't be surprised if he makes a lot.