Society can appear as a great Ponzi scheme at times. In the days of flat population growth this was still true in the tiers of classes or castes. Today in the unindustrialized nations it is also in age demographics, many more young supporting the dream of their future prosperity in the form of the elderly.
In a society that claims "social mobility," residents must see more desirable positions as attainable, though few may have them, so even fewer may actually make such a shift in their lifetimes. In these conditions we see the motivation for striving for improvement, as there is something to strive for and strive one must against competition.
A similar thing could be said regarding the practice of expansionist market economics. More so, as class determinants shift in dynamic societies. If wealth is not the primary factor or tied for first, a class structure may not be a Ponzi scheme at all. The dominant economic scheme is predicated on the fact that the flows of value get mired at the top, forming cow bend lakes. However, if the flow is mired that means the people at the bottom have less to pass back to the top, thus the hunger for new markets. This is what the old colonial system was partially motivated by. The end of it and the bipolar order of the second half of the twentieth century meant the United States was able to experience disproportionate growth, only one other major player was competing for markets. Additionally, the South has been allowed to grow in this "neo-colonialism" and add to the global wealth flow. Now more places have become repositories for wealth and there are more people, such that expectations of material prosperity in the U.S. cannot be maintained.
It is time for us as a society to review or concepts of class and success. How much material comfort do we need to feel fulfilled?