Yes, so true. We did this it in my family but mostly for people close to us.
I experienced this in Vietnam also. At first, I was taken aback when a stranger asked me my age because that's not something we do in our culture, especially to women. Then I learned that they only wanted to speak to me with appropriate language. That age hierarchy is important and built into the language. Once I understood I was happy to tell my age. They only wanted to speak to me with respect.
I'm glad you like my post and video. Thank you so much for checking it out.