It is amazing what people in our neighbourhood notice, eh! I had a similar comment to you when Xena was about the same age by somebody who lives halfway up the street. You're aware that people must notice the mad woman walking up and down the street, stopping and starting, treating and praising, standing in frustration as you wait for your dog to remember that you're attached to the other end of the lead, but to have them comment is equal parts mortifying and gratifying!
He deserves it - he puts up with a lot! He's the one who insisted on us having a Labrador as our next dog - so he's the reason I'm here lol .