The real economy is not elastic enough to handle increase in demand instantly. It takes years to train people to do the things that are taken for granted.
Think of it like the developer salaries in the USA when the money poured in, until it stopped.
Generally speaking, money is for bookkeeping among agents that produce and consume value and the production and consumption has natural speed within the laws of physics. When people who move around faster and demand stuff to consume than the people who produce, then you have local bubbles that disrupts the society.
Also, since the output of the people is finite the larger is your elite class the less stuff to consume for everyone. Better have you elites becoming elites because they dramatically increased the production of the stuff they consume(for example, they might have invented the internet and the services on it and improved efficiency of trade or they might have made great music and improved the working conditions of people who work in insulation, thus more people accepted the job etc.). If you have an elite that is growing faster than they improve the yield, then you have a parasitic class that might end up destroyed if grows too big.