Coinstar more than likely programed it to it that way because that machine had a problem. There are accounts of people trying to do this hack by unplugging the cable and it not working. I think it would be unethical also.
I'm not saying what you did wasn't unethical, you just took advantage of what the machine was giving you.
PolishPunisher wrote:This type of activity has been occurring on my local Coinstar machine for sometime. If you select to get an ecertificate and it cannot issue one it offers a voucher for the full amount (0% fee) of the change it has counted. Think about how many people would complain if they wanted an Amazon certificate and were instead charged 10%, not to mention bait and switch accusations. I put about $5,000 through the machine since September using this method. Unfortunately, just this past Saturday the machine was again able to issue ecertificates. Oh well, it was a pretty good ride while it lasted. The machine was clearly emptied/serviced several times over the past five months, frankly, I was surprised the free counting lasted this long.