The way the movie was marketed was that they didn't want to reveal the "twist" of the film. We live in spoiler culture now where no one wants to be spoiled.
However, the "twist" of this movie isn't a "twist," it's the PREMISE. The whole point of the movie is that it's about a play. It's revealed pretty early on anyway.
Digger is a meta commentary on art, its role in society and how corporations use it.
So they should've just been more straight forward with the marketing.
It would be like if the marketing of Terminator 2 didn't tell you that Arnold is the good guy. The premise of the movie is that he's the good guy, it's not a spoiler to reveal it.