My former boss has similar experience with TSA and customs. His father in law runs a farm back in his home country, and he usually goes once to visit whenever he is there. So, technically, he visited a farm which is one of the questions on most immigration forms. As a resident alien without a green card, he usually gets the 9th degree from TSA and customs. He has found, however, that if he checks this box they immediately start grilling him about the "farm" he says he stayed at. Once he explains "Oh no, it's a farmhouse. I visited my father in law for dinner one night. I didn't do any farm work or walk in the fields." they stamp his form and let him go. They never ask (or even check, as far as he can tell) anything else.

Moral: give the agent an easy problem to find, but one with a simple solution in your favor. They will never look for a 2nd problem.