I don't know if you're strawmanning on purpose or missing the point. I also don't think the answer is "the market will just sort it out...eventually."

Of course there is no law mandating Walmart provide a service. There are, however, laws governing how Walmart must treat employees. Part of their bad reputation is that they run afoul of these laws.

I know the anarchist view is to just decide not to shop there. My point is that in a pragmatic sense, consumers in a globalized economy cannot assess all the information to do so, even if it was freely available. The counterargument is that regulators are the better alternative, which is why the Dept. of Labor has fined them in the past to correct that behavior.