In the movie Fallen, Denzel Washington's character, Det. Hobbes, is visiting a death-row inmate previously arrested by him. The inmate, Edgar Reese (played by Elias Koteas), greets him by saying "It's good to see you, Hobbes", and he answers with "It's good to be seen by you, Reese". I'm not a native speaker, but as far as I know, that's not a common answer, so I always understood that as sarcasm, as Hobbes saying that it was not good to see Reese at all, but answering in a way that sounds polite for someone who isn't paying a lot of attention.
However, I just watched an interview with Denzel Washington where he does the exact same thing with the interviewer. He's greeted with "Mr. Washington, it's great to see you", and he answers with "it's great to be seen by you", and because it reminded me of the scene, it got me puzzled.
So, is that a normal polite answer, and I'm seeing sarcasm in it because of the movie context? Is it actually sarcasm and Washington is being obnoxious, although there's no sign of that during the interview? Is it just a coincidence, or a pun?