Purple Rain Monkey, please don't get pissy. You have posted your question on a "forum" and this is what forums do. The fact that this one is so spectacular at generating helpful and thought-provoking conversation appears to be lost on you. Stop grousing, please. If you snipe at people, they will stop trying to help. Ever hear the saying, "Take what you need and leave the rest?" Here's your chance.
Cali, you crack me Up! It's much easier to get the dog to understand than the owner. Brilliant!
And pkb (I think), if our dogs double poop and we're outta bags, we simply untie the bag and fill it some more. We use a little pouch that holds a tiny roll of bags, which clips to the leash, so this rarely happens any more. And no, we don't carry the used poop bags either. We slipknot them and clip them onto the dog's harness until we get to a public trash can or home. Doesn't bother the mutts in the least.
And I saved the best for last. Our homesite was once owned by a cement contractor. We have a reasonably attractive, low concrete pillar and wrought iron fence, complete with cute garden gate. (I am sure it was expensive, even if he DIY'd it.) Every dog in our universe pees on the pillars. And then our dogs race to the pillars every chance they get to sniff, then pee over the offender's trail. It's comical.
Here's another possible mustachian solution if CN's is not to your liking. Distract yourself. Stop noticing. Stop caring. Deal with it and don't give it any more brain space. It is certainly as annoying as you let it be. It's also a FWP. Reminding yourself of your privileged status might help. Or not. Your choice, but don't flame me for using this approach, because it works, too.
P.S. We walk DH to work in the early, early the morning. There's a neighbor who walks his dog then, leash in one hand (sometimes), coffee mug in the other (always). Took us a while to realize that he was the reason some neighbors have stupid "No Pooping" signs. Yeah, we're not doing that. We figure the dog won't live forever.