Graffiti-art in Bathrooms

I always wonder about toilets with graffiti-art all over the walls. How was this look achieved? Is this something one member of staff did to encourage customers, who then progressively went wild all over the walls, fixtures, doors, rubbish receptacles and even the toilet seat itself?

Or is it all staged? I wonder sometimes.






These were taken at a pub near Harvard Square in Cambridge, MA.