To me it's much more shocking to what great length you go to defend the rights of the company. It seems to me that freedom of speech should come before the right of firing at will. Or is your opinion that companies are about as souverign as states?
My company requires that employees not speak with the press unless they are granted direct permission to do so and that they should, instead, refer them to an internal rep who will speak with them. That is not censorship. That is my company looking out for their best interests so that some dumb ass like me doesn't say something stupid that misrepresents them. My company also has the right to tell me to watch my crude language while working for them and not to dress like I'm attending a beach party.
There are already whistle-blower laws and protections to address what you are referring to, which is the exposition of unethical or illegal business practices by an employee.