The fraud of “buying” an item that you do not plan to keep is very different than the USA coin program. In the former you are causing real and quantifiable monetary damage to a store, the same as smashing the glass in a display case.
With the USA coin program you are going along with a plan to “push” dollar coins into circulation and get some of them into the hands of collectors. They are giving you an incentive of getting a free loan of the face value from the day you actually recieve the coins until your credit card payment is due.
Most of the world has accepted the use of coins for monetary amounts of about a dollar. In Israel the lowest paper money amount that I used on my last trip there was 20 Shekel or about $5-6. Getting Americans to give up the paper dollar for a coin does not seem easy. The fact that they lifted the quantity limits for the dollar coin program probably means that not enough people were subscribing to the program.