I have absolutely no doubt there is some PR behind the decision, but it should also be cost-effective in the long term.
My point was not to assume that this makes sense economically just because Apple did it. They have other ways of getting their money back and if they lose, it's just a rounding error http://finance.yahoo.com/q/cf?s=AAPL&annual
You sure have seen the Beyond Petroleum ads, haven't you? http://www.environmentalleader.com/2008/01/15/beyond-petrole...