The Wall Street Journal did an interesting study on how ethical a company has to be to yield increased sales. As it turns out, "not very."
The Journal defined "ethics" broadly as "socially responsible," and then set about trying to determine just how socially responsible consumers demand of a company before they'll take their business elsewhere, and at what point the value of social responsibility tapers off:
It seems that once companies hit a certain ethical threshold, consumers will reward them by paying higher prices for their products. Any ethical acts past that point might reinforce the company's image, but don't make people willing to pay more.
I found this intriguing, in large part because I think many software vendors try to do "just enough" in terms of open source to ride the open-source wave of hype, but try not to do any more than this. Perhaps this is a good strategy from a purely economics standpoint: There may be no shareholder benefits from being "pure" open source. Being pseudo-open source might do the trick.
That said, for me there are plenty of other reasons to invest deeply in open source, some pertaining to how it makes me feel about my job, but others about how efficiently it allows me to do that job.