I totally agree with your interpretation of the relationship between unethical/ethical behavior and bad PR, but you seem to be ignoring the opposite side of that coin. I hope this doesn't come off as combative, but I felt the easiest way to illustrate my point was by rewording your post:
> The only way ethical behavior affects profit is when it causes projecting the appearance of being an ethical company to become less expensive. To whatever extent that "people" prefer doing business with companies that they see as ethical, what they see is a company's image and branding, not their actual behavior. The balance is between ethical behavior and PR costs, not ethical behavior and unethical behavior; and that's even a gross simplification, because unethical behavior doesn't immunize you from good PR.
Maybe the effects of good PR can be less easily measured and felt than the obvious and immediate repercussions of bad PR, but the effects are certainly real and build up with time, so reasonable people can disagree as to what degree a company should pursue building up goodwill through ethical (likable) acts. Ethical decisions and behavior is the foundation upon which good PR is built. Even the most obviously opportunistic PR stunt must have some backing in an action the company has taken that can be construed by their audience as doing good.
> The only way ethical behavior affects profit is when it causes projecting the appearance of being an ethical company to become less expensive. To whatever extent that "people" prefer doing business with companies that they see as ethical, what they see is a company's image and branding, not their actual behavior. The balance is between ethical behavior and PR costs, not ethical behavior and unethical behavior; and that's even a gross simplification, because unethical behavior doesn't immunize you from good PR.
Maybe the effects of good PR can be less easily measured and felt than the obvious and immediate repercussions of bad PR, but the effects are certainly real and build up with time, so reasonable people can disagree as to what degree a company should pursue building up goodwill through ethical (likable) acts. Ethical decisions and behavior is the foundation upon which good PR is built. Even the most obviously opportunistic PR stunt must have some backing in an action the company has taken that can be construed by their audience as doing good.