Ah, I see that you erred on the side of peace. Good work. Most times, it’s really not our place to tell someone to follow the rules. I do pretty much the same thing when I see people flouting the law. In serious cases I just call 911 and take direction. Those people on the other end of the line deal with this kind of stuff every day.
Long ago, I used to attend a weekly group therapy session where one woman was always late. And she always brought her dog with her. At one point, she was gently confronted about being late and she revealed, with some coaxing, that she just wanted the attention.
The lady you saw in the park with the unleashed dog? She knows the sign that you wanted to point out to her. She’s seen it. She also derives a little shot of adrenaline in the act of committing an offense *and* getting away with it. And you know that if you confronted her, your body would be flooded with endorphins. It’s really hard to think when we’re high on the drugs made by our own brains.
So I think you did the right thing. Don’t worry to much about it. Natural consequences have a way of coming around, you know, like Karma. Perhaps the next time you see her, instead of giving her the attention she wants, take notice of something else. Enjoy the park, instead.