Elves do not rely on money in the same way humans do. While money is exchanged for goods and services, it is not a driving force in their society and is not a factor when considering social classes or nobility. Elves are given a birth fund with more than enough money to support them comfortably through life, and money seems to have no real value in the Lost Cities. They can pay for things using a small green cube (Treasury Cube) that they scan on a gadget called a Deducter.
With their birth fund, elves are given five million lusters at birth, supporting them throughout their lifetime. (Though money doesn't mean much to elves in their indefinite lifespan)