Opinions on picking up dog waste on walks when it’s liquid or diarrhoea?

I know this post is older but my dog had liquid shits on her walk today and I'm honestly not sure myself. An older couple with their tiny laptop looked disapprovingly at me because I left some shit in this grass, but it was like... I got her to the grass, and I can't exactly pick up liquid poop with a bag, so I'm not sure what you wanted me to do? The grass wasn't even someone's yard. She didn't poop on the sidewalk, it's a place where no one is going to step, and I couldn't exactly pick it all up, so? Not sure what some people expect.