Okay, I took a screen cap to demonstrate my thesis. Here it is:
This is from about ten minutes into episode 2. Jerry's parents are sleeping on the futon couch, which has been pulled out. As he enters, Jerry says "This is what I like see, you come home, your parents are in your bed."
They then proceed to have a conversation about how Jerry will be staying at Kramer's apartment while his parents are in town...because the futon couch is Jerry's bed because THERE IS NO BEDROOM.
I rest my case.