Agreed. The money will quickly flow back through the system anyway, and will end up as a profit for some company somewhere. People don't just sit on their meager cash.
Except that much wealth is created in capital growth, for example real estate investments. If someone has a property worth $500k and another has one worth $10mil then the value created through inflation means the latter gets a far larger real growth in wealth. If someone chooses to by the latter house (without credit creation via borrowing) then cash is being absorbed and not flowing back.
The real problem with the whole Wealth, Work and Equality conversation is that there is enough resources and productive effort to produce a generous life fore all humans but we don't have an equitable system that shares it.