Economics professor Thomas DiLorenzo takes a dim view of them here, arguing that “business ethics courses tend to cherry-pick isolated examples of unethical behavior in the business world and insinuate that such behavior is inherent in all business. This ignores the reality of how markets work and misinforms students. . . . Business ethics courses typically combine anti-business moralizing with advocacy of more government regulation of business and, subsequently, a greater politicization of society.”

Those are broad claims, but I suspect they’re generally accurate. This strikes me as a good field for some research.