One way those who want to "improve" the free market do so is by introducing competition in the form of a government program or agency that duplicates work done outside the government. Usually those in the afflicted field would be surprised to know that the field doesn't currently have competition. But in order to correctly analyze the claim, it is good to look at fields where the government directly competes with private enterprises.
First and foremost on any list of government activities that compete directly with private endeavors is education. At one time education was largely private, and to a great extent taxes were not used to pay for education. Yet education was available at all levels, although non-compulsory, to the point where religious groups were even offering free education to the poor. But government sponsored education has only increased. Since it is paid for by taxes the direct consumer does not directly pay for the education and therefore mistakenly considers it free.
As a result, private schools have diminished in number. While they generally provide a much higher level of education, only those who are either make major sacrifices or are wealthy can take advantage of the better education offered.
The second endeavor to be examined is in delivery of the mail. Libertarians are generally familiar with Lysander Spooner's attempt to deliver first class mail, and how the Post Office used legal coercion to shut it down. Package delivery still has private competition in the form of UPS or FedEx.
The prices for package delivery by the USPS are lower than UPS or FedEx, due to undercutting. The low price is supported by raising the rates on first class mail. Even with that undercutting those who can afford it (and in this case many but not all can) prefer to use FedEx or UPS. What makes the USPS special among cases of comparing private and public offering of services is that the user does pay for the service directly. But even then the USPS is subsidized by the Federal Government.
Another is the providing of security. It is well known that the rich do have private security in private communities or residences that respond quickly in the event of a disturbance. Those who are of average means can afford to defend themselves by the purchase of a firearm. Those who cannot afford any better rely on the police, who arrive after a crime has already been committed to make the report and try to apprehend the criminal. The rich have proactive protection, the middle class can protect themselves, and the poor have no protection.
The building of roads has been entirely taken over by the government to the point where many cannot imagine it being any other way. In the former Soviet Union people could not imagine how shoes could be distributed if the government did not do so, and wondered if those who thought a free market in shoes meant that only the rich could get shoes. There is nothing to compare the building of roads to, given that the ability of government to force everyone to pay and offer the resuliting roads for "free" has completely driven private roads out of business. Those toll roads that are managed by special grants from the states do not count as they are not free market but are corporatism.
In every case except the Post Office, the ability to force payment into the program, combined with while offering the service for "free" has driven competition out of the market for all but the very wealthy. The same is true to a lesser extent for the Post Office. This has resulted in only the wealthy being able to truly afford high quality goods or services.
The health care plans offered by President Obama include a "Public Option" where the Federal Government directly competes with private insurance companies. If history is any indication this will result in only the wealth being able to afford high quality medical insurance. Taxes will be raised to provide the service, and the public will be lied to about how the service is free. Those who advocate anything other than a program which will result in only the rich being able to afford quality insurance will be accused of wanting a program which will result in only the rich being able to afford quality insurance.
I'd like to welcome as readers the Complete Liberty Podcast, as I've just discovered that they've used two of my articles in their podcasts. I'm flattered.
Edited to add:
A critic of this article pointed out that education is somehow disproof of the proposition that public and private competition leads to only the rich being able to afford quality services. What was offered as proof wasn't primary education but colleges, which in the United States are still considered to be very good.
It is true that on the level of Masters or Doctorate the United States is of exceptionally high quality, and in some fields a Bachelor's Degree is worth more than the paper it is printed on. But as is being pointed out on Lew Rockwell's website the cost is becoming prohibitive. Students graduate with many thousands of dollars in student loans just for a Bachelor's, after scholarships and grants. Those who go for even higher degrees finance it almost entirely by borrowing. Education is becoming a way to become an indentured servant of the lending agencies.
It is true that a Bachelor's Degree holder statistically earns more over the course of his life than someone with only a High School degree. It is also true that the costs of paying for that degree are rising to the point where they may be higher than the lifetime earning differential. If that happens than the economic decision would be to forego higher education.
That would mean that thanks to public versus private competition a quality higher education is only the rich can afford.