Q1: Is there an allegory or double entendre in the Wasteland?
It is literally a wasteland because of the garbage. However, there seems to be an underlying metaphor that applies to the people living there, how society perceives them and how they perceive themselves. Many of the pickers are people who have had unfortunate circumstances that led to them moving to the landfill. While many of the pickers take pride in their work, some of them, as well as society, perceive them as garbage.
Q2: Is there an underlying message in the film, revolving around the celebration of things and people who have been deemed useless?
The artist’s work takes the concept of making garbage into art, both actual garbage and people perceived to be garbage. The art says that these people are worth something and that they are praise worth contributors to society.
I think it should also be noted that most, if not all, of the pickers are people of color. While racism is not directly addressed in the film, there is something to be said about the way people of color are celebrated in this film, and how their beauty is brought out.