Your interpretation, is not entirely objectionable. And now my subjective interpretation: The economic prison we live in creates the need to express our objections to the reality of ever changing conditions. IMO most art tends to be some form of protest. Banksy does good work, though he is not alone, but I fear he has been embraced by his wealthy art overlords, Here is hoping they develop a conscience, but no guarrantee. He is already quite well known, though I suspect that his run won't end in death, like a Basquiat. I like these modern cave paintings spread across the world... it seems much more like a growing organism, like a some sort of intelligent bacteria gasping for air while searching for more space to expand and fill.
Oh well, and it's just paint on walls...