Precisely. A free market cares about one thing and one thing only: efficient use of resources to satisfy demands. It doesn't care about who is making the demand - only in how much their market is willing to pay for a specific good/service and the overall size of the market. Racists by their very nature limit their potential customer based and inflict on that customer base higher prices as a result.

"The bottom line is that racists cannot trust free markets to racially discriminate."
I think the market pushes people not to discriminate.

Today one of the "more respectable forms of law" that produce similar results is minimum wage laws.
Walter Williams is one of todays heros.