I didn't mean the theme. I just meant a theme. Also, if I recall correctly, the phrase "what's going on?" is muttered throughout the film as well. So I think it's a little of both (and more), where the more global theme is one of trying to understand understanding.
Although, I think a lot of the analysis of Coen brothers can sometimes fall flat. Coen brothers films are hilarious, often in extremely dark and non-obvious ways, so oftentimes their films are overanalyzed. I often think answers to "why did the Coen brothers put this in the film?" are simply "because they thought it was funny".
There's a phrase that's repeated again and again (in one way or another), which is "but I didn't _do_ anything".