Haha - having spent lots of time with the older generation, I would guess the lady didn't phrase her quesion to ask what she intended. I would say that if they take the time to ask, then they are not judging you and walking to the other side of the street so try not to be aggrevated and just tell them that there is no real meaning to it, it's just decoration.
I work with the public, but never realized just how ridiculous people can be about not respecting personal boundaries until I got pregnant. People do not hesitate to tell me I am big, small, touch my stomach and ask about a million other personal questions. The kicker is that people seem offended when I dodge their attempts to touch my stomach.