I will never forget when I visited Paris as a tourist and in the green patches of grass in front of the Eiffel tower where everyone sets down their blankets and takes selfies is littered with Heineken bottle caps and cigarette butts, it was so uniformly covered in the things that I took a picture of it to remind me. I sort of got that Heineken and smokes are super popular there (at least amongst the touristy areas) but still.

May be the non-touristy areas are also considered dirty by you, but I'm an American, where we treat public places like shit but make sure interiors and the entrances near parking is pretty and the rest of the fucking street is trash since no one other than me apparently walk it. To me, the "grime" I see seems normal if not a little nicer than any city in Ohio.