Big News Distraction of the Day: it costs more than a penny to make a penny! Oh noes!! We needs cheeper pennys!!!!
As PTerry pointed out: the penny gets spent more than once. Many times more than once. Coins circulate. A spent penny is still a penny, and the new owner can spend it again, and so on. The initial cost of making it is of little consequence.
Now, having the currency debased to the point that the metal content of a coin is worth more than the face value... that's a problem. That's why modern pennies contain almost no actual copper, and dimes and up no longer contain even a hint of silver. But I don't think we're there with zinc pennies. Yet.
(The utility of the penny in this age is another question entirely. The cost of minting it is a red herring, though it costs several pennies to buy one herring of any color.)

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