Doubtful. Credit card companies charge a percentage of the transaction cost to the seller. Usually sellers just mark up their goods accordingly, so the buyer

Doubtful. Credit card companies charge a percentage of the transaction cost to the seller. Usually sellers just mark up their goods accordingly, so the buyer is the loser. The buyer's only recourse is to use a rewards program to get some of that markup back. The credit card company lost little if anything, and probably profited on the transaction. The mint was eating the entire credit card transaction cost, so that $300 came from the mint, and probably more as well. Not to mention the shipping charges, and the cost to re-process all of those coins when they came right back to the mint. The line item profit to the mint is still positive since it cost way less than $15,000 to make those coins and they can re-sell them. But in reality, it just means that either the mint prints more dollars to make up for the loss (taxpayer loses in inflation) or more taxes are raised to pay for the loss (taxpayer loses more directly). The bank where he deposited the coins also was forced to eat processing cost and shipping charges to return the coins to the mint. If lots of people started doing this, the bank would end up having to raise rates, charge for the service, or put significant limitations that would hurt legitimate usages (ex: laundromats). All in all, this is a naughty hack. The hacker came out ahead, the credit card company came out ahead. The bank lost a little, the US government and taxpayer lost big. The economy as a whole loses as well - a lot of busywork was created, but no net value.