If it is true that too many people living in an area causes degradation and a destruction of natural resources, then why is it that people who live in the large metropolitan areas in the united states able to have so many more material possessions than those living in the countries to the south of us?

They many more material possessions because of the economy of the region.

Explanation:

Every state has its own economy. Mainly, best economies are located in metropolitan cities, there's concentrated the money of companies, for example. The opportunity to get a job is higher and this able people to buy stuffs. In the other side, cities where companies don't invest, there's not gonna be cashflow, neither people receiving good payments.