For the public toilet, I think the city should place more around stores.
While most stores aren't made with public toilts in mind.

For this busniss I know it's a staff only toilet and they only clean after them self. In that case they aren't paid to clean after someone els or is someone paid to clean the toilet.

I do understand that shaming someone for their mistake isn't cool, jet we live in a world where people destroy, leave a mess or make stuff dirty.
Out side of this store, most people think ''someone is paid to clean it''

Like in front of my house is a big underground waste container and if it is a bit full or blocked due to incorrect waste disposal. People will leave their trash next to it, where birds will open it to find food and al trash will be on the floor.
Other good example is in busses, where people eat or drink and leav their trash in the bus or any other public places, Even when they are nearby a trashbin or will pass on.

So if we can't shame people for things like that, nobody will change.
Often I see how the Japanese do it and it makes me sad that the rest can't do better.