[lottin]

You're mistaken. Most economists understand the difference between a free market and a black market in the same way that I do (I am an economist myself). The very definition of free market that you quoted implies the existence of a legal framework and of an authority with coercive power, since some behaviours are prohibited:

"In a free market, the laws and forces of supply and demand are free from any intervention by a government or other authority other than those interventions which are made to prohibit market coercions. Examples of such prohibited market coercions include: economic privilege, monopolies, and artificial scarcities."

Further, a market in which fraudsters can commit fraud with impunity is also not a free market but a dysfunctional market.

At any rate, the notion of free market is only vaguely defined, as it's not an important theoretical construct in economics.

As far as crypto-currency markets are concerned, these are not a single market, but many different markets, some of which are heavily regulated, so it's hard to argue that it's a free market.