Last year I purchased an air conditioner at Costco, sent in the $20 mfgr's rebate form, and within a week or two of my purchase, decided to return the unopened, unused A/C to Costco because I just didn't need it after all. When the $20 rebate check arrived in the mail a few weeks later, I sent it back to Costco. To me, keeping $20 for something you are fully refunded for is no better than stealing. It is simply unethical and wrong and anyone who says otherwise is deluding themselves. That $20 comes from somewhere, and ultimately everyone's prices will rise to reflect the loss of $20 multiplied by the number of unethical people who decide to pocket it. The end of the story is that a few weeks after returning the check, I actually received a thank you letter from Costco saying thanks for returning the check, and praising me for being so honest and doing something that most people would not do in this day and age. This token affirmation that I am an honest and ethical person was worth far more than the lousy $20 would have been. Sadly, I am sure I am in the tiny minority on this issue.