Paying people is only net zero if the people being paid go and do the same thing the people paying would have done with that money. In this case, I'm arguing b

Paying people is only net zero if the people being paid go and do the same thing the people paying would have done with that money. In this case, I'm arguing because of the economic class of the ditch diggers that this is not the case. The ditch diggers will spend the money locally, rather than saving it, on things that give them greater utility than what the people paying for ditches would have gotten (which is most likely just saving it). I agree asking people to dig ditches for the money is stupid, but in reality they'd either be doing something productive that wouldn't have otherwise been done for structural reasons (building national parks, windmills, solar panels, etc., things where there is a positive externality that prevents the market from doing it) or receiving the money for free.