The fact that it could be something else is, I think, largely irrelevant. Any picture could be pretty much anything. If we make the simplifying assumption that the photographer had something in mind, then we should probably spend a little effort looking for it. This picture rewards effort, to my mind, and that is a good thing in a picture.
That said, we always walk a narrow path between being too obscure, and being too obvious. I like pictures, and I like looking at them, and I enjoy trying to puzzle out what the photographer had in mind. Others, less so. So, to please me you arguably have to be more subtle, more obtuse, whereas to please others you need to be less so, and still others probably want your pictures to be even more opaque.
I personally had no trouble seeing what this picture was about, and I had no trouble suspending my disbelief enough to imagine that I was seeing a luxury car and a poor man. Whether that's really a luxury car, and whether that's really a poor man, is irrelevant to me. The picture is clearly intended to illustrate the contrast between a poor man and a luxury car, and I was willing to accept it as a depiction of that (whether fictional or literal, I don't much care).
It is quite clear that other people are unwilling to so suspend disbelief, though, and that's good information too.