That would most likey be me..... I worked in a Haunted House for 13 years and last few years got to design one each year. And yes I liked the effect of live creatures.A few years ago there was a thread about cockroach rooms.
One guy posted that he had built his room out of plexi-glass and then raised live cockroaches and put them in between the plexi-glass and outside walls (Including under the floor).
He said it was a lot of trouble raising the cockroaches, and probably wouldn't do it again - but it was very cool!