According to that same article about the World Bank, real estate and gold are also "naturally occurring ponzi":
If people believe housing prices are bound to go up, they will beg or borrow to buy a house, thus creating more demand and contributing to prices spiralling out of control
Gold is another example, as it has witnessed numerous bubbles and crashes over the years. Basu notes that gold lost more value in two days of April 2014 than it did in thirty years
Of course in the exact same article the report states:
Basu stresses, however, that bitcoin is not a deliberate Ponzi and that there is little to to gain by treating it as such.