Libertarians living off tax money is unethical, but it’s an even bigger practical problem. It shows that living without the government teat is impossible, that living on theft is the only way. It is philosophically damaging to the idea of a voluntary society. It is also bad marketing to people who ask questions like “who will build the roads?”
There will never be a day when we simply “get rid of government”, such that everything is perfectly free. This is because no one wants to be the first to give up their government goodies. Just as unilateral free trade is better than mutual protectionism, unilateral voluntarism is better than mutual theft. We can only ever get rid of government by showing, in practical terms, how to make a living without it.
Is it difficult? Extremely! Will it mean less money and fewer opportunities than working for the government? Yes! That is the price of advancing liberty. Many people are not up to the task. But then don’t blow hot air about liberty, if you are unwilling to do what is required to bring it about. It reeks of hypocrisy. The pioneers of liberty are the ones who show how to make a living, or even be rich, without stolen tax money. If they show the way, others will follow, simply because it’s in their self-interest. And isn’t that what we say motivates people, rather than abstract principles that contradict their daily reality?