Why is it that Americans are the only major country with all of the currency being one color?
We've found that it's so hard to counterfeit the paper that most people have been taking smaller American bills, and changing them to look like bigger bills. Now that our currency will be multicolored, it will be far harded to remove the ink and recolor the paper to try and change the denomination.
Plus, at a simple glance you'll know what the bill is.
I've actually argued a few times in my life with a cashier that I just handed them a $100, and not a $10. With colored currency, you don't have that problem.
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"Nihilism makes me smile."