I was looking through the pictures my mother hid from me. I WAS "smiling" in some, but only ONCE a full smile, when I was like 7. My mother always made a note when I smiled, and told me that WA because it was rare. Maybe it was easier with some of my teeth out, who knows. Anyway, in MOST I look miserable, and at one am looking NOWHERE near the camera, and they are ALL "posed"!
The smile means NOTHING! I smile, such as it is, when I am happy, laughing, pitying something, frustrated, angry. In the same cases I may also give an appropriate response, or none.
As for the guy at the beach? Tell him to GO TO HELL! He has no right to ask that, especially in such a case.
Steve