In my travels, when I go through immigration at a point where I am planning to spend a few hours before flying onward (although typically not back to my origin), I will write "transit" in the form where it asks for my local address. I have never done that in the US, so I don't know if this would be appropriate advice for the OP. My guess is that it might be at least as appropriate as writing "SFO" on the form.

I do, however, like gre's advice of engaging the officer in a discussion that will cause him/her to want to be rid of you quickly.