Do they? It's by far the largest BTC exchange - by a factor of ~50 or so. If you want to exchange more than a couple hundred BTC, they're the only game in town right now.

Yes, but they're the only big game in town not because they held a gun to anyone's head or threatened to throw their customers in jail if they dared to start using another exchange, but because they provided the best service. They did not engage in coercion. This is the heart of the free market and of anarchy.

It is the heart of the free market but it is not the heart of anarchy. Anarchy would happily employ coercion. After all theres no one to stop you when anarchy reigns. In anarchy the big dog wins until a bigger dog comes along.

Please don't conflate the free market with anarchy.

"Anarchy would employ coercion"?

You should read up on the foundations of anarchy before spouting your mouth off, since you are woefully ignorant on the subject. Bakunin, Kropotkin, and Bookchin are all good places to start.

Perhaps anarchy the philosophy would not employ coercion. But anyone in an anarchic society would happily employ coercion. That's what I meant when used the poorly phrased sentence "Anarchy would happily employ coercion".

Coercion does not have to be done by a governmental entity. The philosophy of government can wax as poetic as it wants but I know too many people who would happily take advantage of anarchy to employ said coercions. Practically speaking, Human nature being what it is, coercion will be rampant in an anarchic society. I'm quite familiar with the foundations of anarchy. I just occasionally use poor wording :-)

You can't unsubscribe yourself and your property from the government services, but you can from mtgox. That's the difference.