We know that, but the countless folk toiling at Enrons, Wal-marts, Micro$ofts, etc. are convinced that the market is their road to personal success and freedom from the tyranny of their boss, if they can only make it....
The appeal of the market ideology - like that of communism and religion - is that it is an eschatology, a promise of personal salvation through a seemingly rational system (as opposed to personal favors) that in principle anyone can understand and follow. That impersonality, rationality and nominal openness to all is the main attraction - it is a very promising alternative to personal or anthropomorphized relations in actual institutions - with their bosses, rules, government regulations, restrictions, "tax burdens," etc.
In that context, a system that is impersonal, open to everyone, and rewarding merits and hard work looks indeed as a very attractive promise vis a vis that institutional reality. Of course, the promise is false - just as the countless promises that religions and mountebanks all over the world make - but it gives hope and "makes sense," so people find it difficult to resist.
Criticizing capitalism is like telling the downtrodden folk for "found Jesus" that there is no god and heaven and their suffering will not be rewarded in another life, because there is no such thing as "another life." It is taking away the only hope these poor schmucks have, and it is obvious that they will not give it up easily.
A better way is to offer them a superior alternative. Instead of criticizing capitalism and the free market mantra, offer an alternative vision of the economy and society free from the tyranny of profit making and racing to the bottom. Such alternatives already exist, e.g. http://europa.eu.int/comm/enterprise/entrepreneurship/coop/ The trick is to spread the word to the folk who are now attracted by false promises of the market for personal success and religion for community and solidarity. Social economy offers both in one package.
Wojtek