This is part of a new AA customer security screening process. A friend, who works in check-in for AA in London, told me about it. The idea is that customers, "who have nothing to hide" will act normally; and people who have something to hide won't want to answer the question and will act nervous etc.
And check in agents are taught, in training, to notice the difference between people who don't want to be asked personal questions and people who don't answer the questions and shouldn't be allowed on the aircraft.
Also check in agents have to change the questions asked from passenger to passenger. And the training was rigorous for this new security screening.