I’ve noticed non-libertarians will frequently make the claim that liberty-lovers are hypocritical if they use things that are paid for with taxation. What an odd notion.
As long as The State exists, and continues to fund things through coercive taxation, you and I will be paying for a lot of things we didn’t have any choice about funding. We are forced to pay for public schools, libraries, museums, and public roads whether we use them or not.
In some instances, such as roads, it is impossible to avoid them, so there is no hypocrisy in using what you pay for. If you are paying for something, you may as well use it. How could anyone have an objection to people using what they are paying for?
This is not the same situation as welfare, which involves people using things that others, not they, were forced to pay.
With government programs you are forced to pay even when you are allowed to use a private alternative. In this case you end up paying twice — once for the government service you are opting out of, and once for the private alternative you are choosing. Yet, people still make the choice to pay twice, on a daily basis, in order to get what they really want and need.
There is nothing carved in stone saying that using public schools, for example, is against any purported libertarian commandment. I do not think public schools are the best choice for educating your children, and in many (or most) cases I think they are actually harmful. However, as long as you are being forced to pay for these schools, you may use them with a clear conscience. If you feel any guilt, it is between you and your children for handing them over to The State for the majority of their formative years.
The same goes for any other service provided by The State. Everyone should have the choice of what to fund and what to use. No one should have to fund the things I choose to use unless they want to.
The hypocrisy is in pretending that it is OK to have a government monopoly, or to force people to pay for something twice if they wish to use an available private option. Opting out of the government option, including not paying for it if you choose to not use it, must always be allowed.