Fine, you feel you're not being robbed. I know quite a few people from the US who feel that taxes are theft. Granted you agree they have the freedom to believe in whatever they want, how do you justify the fact that if they don't pay taxes, they will go to prison (not right away, but eventually, if they decide to resist, even if peacefully) or have their property alienated? Democracy isn't the answer, because they don't believe in one. If you say they have to pay because they use services a government provides, then it's also very debatable: they certainly may not want to pay for some of them (military?) and surely they don't have any alternative because government monopolistic behavior prevents any competition in certain sectors of the economy. Saying they have this freedom to believe in whatever they want when they don't have the same freedom to act according to their beliefs is identical to not granting them any freedom at all.
I justify that by pointing out that they are free riders. There are surely people living on backwoods property that pay little to no tax, because they are effectively not part of our various collective enterprises. Godspeed to them.
But if people want to enjoy the benefits of living in a city, state, and country, to participate in an economy, those benefits come with obligations. Sure, they may not want to pay for things. But if they can't get others to agree that the government should not do those things, or at least should run them on a cost-recovery basis, then it's too bad.
They certainly have the freedom to move to someplace without effective government. E.g., Waziristan or Somalia. They will be much freer there. Of course, warlords will be free to rob or kill them, so it may not be entirely to their tastes, but then, we aren't guaranteed perfect choices, just the opportunity to make better ones.
