Milpitas Dog Park

I hate not knowing how to handle situations. After cleaning up 2 poops that weren't ours this evening, a couple walked in with two dogs, one of which pooped on the grass near the gate. I tried to get their attention but they were in conversations with people about the dogs so I waited till they finished and pointed out where the poop was. They turned away and started talking again, so I went back to play with my dog. When we decided to leave, I got the woman's attention and again pointed out the poop. She snapped at me that they were dealing with it and leave them alone. Neither of them had poop bags. When I said that I really didn't want my dog or myself strapping in it, the husband want to get bags and then their dog pooped again. I pointed it out to her and the husband came charging up yelling at me that they weren't in third grade and I should mind my own business and they had come up for a nice peaceful evening and I had ruined it for them. My husband stepped up and pointed out that we had waited over five minutes and neither of them had done Diddly to clean up the mess their dog had made. We then left. I'm stunned how quickly a friendly attempt to help them by pointing out where to poop was ( since I hate having to hunt when my dog poops and I can't find it) escalated into them shouting at me. How should I have handled i?