Making graffiti by cleaning dirty walls... The guy finds a legal and harmless way to put something interesting in a public place and they ruin it pretty much right away by cleaning something they havent bothered to clean for years. (Sometimes sadly thats the only way to get something done though.. (Cleaned,etc))
I am against graffiti but this I do approve of.... What he was doing was HARMLESS and if they had done thier jobs and cleaned it,he couldnt of done that now could he?? Ah well.......
I think that's pretty clever. It is harmless as Dude111 said, and I think it almost even makes a statement. If his goal was to get them to clean it, I guess he succeeded. Nice find.