You wrote that it is an inalienable right that "I have the right to use my labor either by exchange or in charity." I contest the notion that it naturally follows that it is also an inalienable right that I have sole ownership of what I exchange my labour for. The state, through its laws, has afforded me certain rights as a worker to fair treatment by my employer, including a minimum wage, which dictates the minimum value of my labour. Without these laws, the value of my work would be arbitrary, and I would be at the mercy of the whims of my employer. For the state to functionally continue to protect these rights of mine, it needs income to sustain itself. Since I benefit from this function of government, it follows that the government has a right to claim part of my wage in order to sustain itself, and continue to protect my rights as a worker.
Indeed. I believe minimum wage laws and labor laws are unjust as they make the claim that they can decide what's best for a business rather than voluntary contract. This isn't to say I condone unjust treatment toward employees, but I believe the State often causes more damage than good. Prior to programs like OSHA, the safety and treatment toward employees were rising in positive ways. When OSHA was introduced, it was like someone jumping in front of an already-in-progress marching band and started to lead it. However, with minimum wage laws for instance, it might mean while one person gets an increase in wages, another person gets fired because the business can't afford to pay both people. This is only a short, basic explanation for the downside to it. There's more to it than that.
If we are saying that it's our right to exchange labour, and this is our means of income, we should also consider the ethical implications of the fact that not everyone is able to offer labour. The elderly, the sick, people with disabilities, etc would have no "right" to own property (like monetary wealth) since they cannot offer labour.
When I say labor, this is only one example. Labor could mean physical labor, but it could also mean time, ideas, creativity, etc. etc. In a word, employment.
Though you are right that there are some people completely unable to work--people in vegetative states, the bed-ridden, etc. This is why charity is so important. Charities, despite fluctuating economies for many years, have provided aid for these people. But even in the midst of bad economies, people have overwhelmingly given to the needy. If the income tax for instance was abolished, folks would (and have according to the Consensus Bureau) be able to provide that much more toward charities.
When Hurricane Sandy struck, a lot of people were willing to bring in canned foods and start food drives for people. Mayor Bloomberg, however, put a ban on these food drives in May of last year because of the salt content. Granted, charity was still offered and provided, but it could have been much stronger if the mayor didn't prop up a nanny-statist regulation.
In short, everyone has the RIGHT to offer their work, but that doesn't mean everyone has the ability to do the work. But for those who don't have the ability, this is why charity is so important, whether it comes from family, organizations, churches, neighbors, or strangers.
And while I understand the argument for subsidies, it comes back to the question of "is it theft?" In other words, does it go against God if we steal from Peter to give to Paul?