Buenos Aires, Argentina, is supposed to the Paris of South America. I dunno, it could be. There is one thing though, that it has in common with Paris and that is dog shit on the sidewalks. I thought Paris had cleaned up their act, but it seems to still be a problem. It's definitely a problem here in B.A., but maybe that depends on your definition of a problem.
Jack has a theory that there are two kinds of dog owners: those who are poop-phobic, and those who aren't. Those who are poop-phobic simply look away when their dog is pooping and ignore it while they go on their merry way. People who aren't afeared of poop will invert a plastic bag around their hand, pick up the poop, revert the bag, tie it off and carry it away.
I am thinking there is something else going on as well and that is cultural conditioning. People who have grown up with dog shit on the sidewalks see it as entirely normal and so see no reason to do anything about it. In effect, they don't even see it. That doesn't mean they will step on it. They acquired dog-poop avoidance techniques at a very young age and by now it is automatic.
Paris is trying to clean up their act again with stiffer penalties and more rigorous enforcement. That might work, but I expect it will become a big fight before it manages to effect any change in people's behavior.
I suspect the only way to really fix the problem is to make dog care a required elementary school class. In about 20 years you should start to see some progress and in 80 years, when all the old poop heads have died, dog poop on the sidewalk should be a rare event.
In other words, watch your step.