I rather think people have a right to privacy, and the employer-employee contract isn't really the business of anyone else.
Sure, why let markets have sufficient information to function properly? Whether or not it is someone's else business should be up to the employee, not the employer who has a policy to fire employees who discuss their salaries.
Why is it that everyone except free marketers believe that a free market needs perfect information to operate?
No one mentioned perfect information, so your observation appears pointless. Markets operate more efficiently when there is more relevant information available.
It is fascinating to see self-proclaimed libertarians argue against markets operating efficiently and against freedom of speech.
Freedom of speech includes the freedom to remain silent. Freedom of speech merely means that the government cannot force you to remain silent. If you think that having a third party interfere in the private contract between myself and my employer is freedom of speech, no wonder you've never understood anything any libertarian ever has ever written.
Saying "what the hell are you third party doing taking my information without the consent of either myself or my employer and publishing it" isn't a freedom of speech issue.
On the other hand, by arguing that the free market needs the information on everyone's salaries - so that people can see what their coworkers are making - is actually a variant of the "perfect information" argument. The market does just fine with imperfect information. Information is a commodity just like all other commodities, and the market efficiently allocates even information.
I understand someone who doesn't believe in markets making the "perfect information" argument, but I don't understand someone who makes that argument without knowing what that argument is.
Seriously, if you're going to keep on criticizing free markets, please do read up on them. It would help your arguments immensely. You really can't argue against a proposition you know nothing about, no matter how well you know the alternative. I see creationists try that all the time, and they always fail because they know nothing about what they argue against.
Plus my comment at the bottom of the previous page.
While I am always up for a good laugh, those comments were neither relevant nor amusing.
Of course having everyone's salary be public would never be an open invitation to criminals to see who has the money and therefore who they should target. There's no such thing as an "unintended consequence."