This is the fallacy that PS workers and their sycophantic unions have been propagating for years, as if the PS is 'self-sufficient' or 'self-financing', the ludicrous 'I am my own Grandpa' argument. Wealth creation is the preserve of the private sector; infrastructure creation and maintenance is primarily the responsibility of the public service using tax money..... It is not just the private sector that pays taxes or pays for public services.
Tom, Dick and Harry work hard in their private sector jobs and pay tax. Paddy is a PS worker and collects the tax from Tom, Dick and Harry and uses it to pay his own wages and provide the infrastructure for all of them. Paddy pays tax but that money came from Tom, Dick and Harry to begin with, Paddy created none of it.
If Tom, Dick and Harry are forced to emigrate, Paddy is forced to follow them as there is no wealth being created at home to pay him or to maintain and renew the infrastructure.
Too simplistic a view, downright disrespectful, cynical? Maybe, but possibly useful in order to maintain some perspective as to the roles that the tail and the dog are meant to fulfil.