This post from All My Own Work! ~ A history of pavement art! demonstrates how visual arts have been exploring other venues for expression for much longer than many people realize, though anyone who has seen Disney’s Mary Poppins, knows chalk paintings are magical worlds until the rain comes.
One of the basic principles of Mass Media, is that as a dominant form of Mass Media loses its place in the media hierarchy, it will adapt or innovate to offer something unique. In the world of colour printing, photography and emerging cinema, visual arts had to offer something new in the way of content/style or presentation, such as production in public spaces.