Wow -- it was unbelievable. We were just across the street from our apartment pretty much, in front of one of the children's playgrounds. I ran into a nice young woman who had a friendly two year-old female (part pitbull, I imagine), who was a little scared of Leo at first but soon developed the confidence to jump on his back several times, to Leo's dismay. Another young woman came around with a smaller, more typical French dog (cute and fluffy), and we all let our doggies say hello. This was a real first for me. Three friendly dog owners with three friendly dogs at one intersection. The odds are pretty slim. The first woman remarked that her dog has very few chances to interact with other dogs. Yeah, no kidding. This is Paris, where most dog owners would rather keep a safe distance from your dog either because they don't trust yours or they don't trust theirs.
These days, I do usually try to avoid any possible negative confrontations by crossing the street immediately if I see another dog coming towards us that might be of the hostile sort (or with a hostile owner). After crossing, I look back at the dog owner and get a huge smile! It's nice to get a thank-you from a perfect stranger like that, but poor Leo has to suffer from fewer doggies interactions.