There's a couple people in my neighborhood who have never used a bag because it's obviously below them. I've left 2 piles in the 6 years I've had my Lab, but only because I didn't have a bag.
I put a sign up in my park because I got tired of it, because the city sure as fuck wasn't going to do anything about it. It was slightly snarky and was meant to make the offenders feel like small people -- and it mostly worked.
I also put 2 wood screws into a tree and used a zip tie to secure a roll of bags. I've replaced it about 10 times since I did that, so at least people are using it. I may have went overboard, but stepping in some dumb motherfucker's dog shit is among the most infuriating things I can think of.
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