This misunderstands Functional Finance. It is not a zero sum game to spend additional money on employing idle resources (labour), rather it expands total output and does not require additional tax revenue to be raised dollar for dollar. One is not “robbing Paul to pay Peter” in that grossly myopic libertarian rhetoric, JG workers are ultimately creating public value for their communities.
What happens is the money JG workers spend stimulates the private sector into creating more better paying jobs producing the goods and services the JG workers consume, which in turn reduces the number of people who end up relying on the JG for ongoing employment.
Additionally the fiscal expansion results in JG workers purchasing more imports, and these imports put some initial downward pressure on the exchange rate. This then results in boosting some employment in export industries which further reduces the reliance on the JG. The increase in imports and increase in Current Account Deficit occurs under all forms of domestic growth induced spending (including private investment), and not an issue for a developed country like Australia which has good export capacity and potential.
At some point if there are supply side bottlenecks which put pressure on inflation, it maybe necessary to increase taxes to a limited extent in target areas as to reduce aggregate demand. This in turn will suppress employment in higher wage private sector jobs and push workers into the lower paid JG bufferstock, thus suppressing wages and inflation without creating unemployment/underemployment.
However strong public investment in education and training would reduce these bottlenecks, in combination with a highly targeted skilled migration program, as does strong public investment in infrastructure which reduces costs and allows leverage of private investment.
The best taxes for suppressing inflation are taxes on economic rents, especially land, since land price inflation is the greatest source of inflation of all, and land is the most scarce resource since its supply is fixed.