Did you watch last night's episode carefully? In the opening scene Larry David was trying on some pants. When the fire alarm goes off, the building must be evacuated. One of the evacuees? None other than Ben Affleck.
Which begs the question: why? None of it was explained throughout the duration of the show. It's like an updated version of spaghetti cat. It's there, everyone knows its there, but no one knows why it's there.