Saw this the other day... by the end you realize just how unimportant most of our cultural differences really are. Economics explain far more about how we really live than the culture we are born into. With projects like this knowing an individuals income will give you some insight into how they actually live.
This is actually a good thing as the world slowly moves closer together up the economic street.
I think it also helps to be aware that within our own countries the differences between rich and poor can be pretty extreme. Keep in mind the overlap between countries, many have houses on both ends of dollar street, so their neighbours can come from anywhere.
