If the state expands, the private sector must shrink
In the last few years there has been a transfer of national income from the private sector to the public sector of about 10% of total national income (therefore of about 20% of the private sector). This has come in two forms. Some of the increase in government spending has arisen as a result of increased welfare payments. This has no direct effect on private sector production because money is simply being transferred from one group of consumers to another: government production is not increasing. However, the welfare recipients will spend the money on different things from those that taxpayers who are paying increased taxes would have bought. Therefore there are additional disruptions to the normal dynamic process of changes in preferences leading to different goods and services being required to meet demands. This is a problem but not necessarily serious.
However, a good proportion of the increase in government spending is being spent on services – especially health and education. This involves a direct transfer out of private sector spending, and ultimately production, to public sector spending and production. There are lots of complexities and leads and lags but, ultimately, a substantial part of private sector production must completely shut down in order to release the economic resources necessary to provide more schools and hospitals (or, strictly speaking, largely more bureaucrats and administrators). The fact that pubs are closing down directly because of a beer tax is simply a more obvious mechanism than the less obvious mechanisms that occur when the state bids in the labour markets for more resources thus raising costs for other employers, ultimately leading to a reduction in private sector production.