[crazygringo]

The article isn't about transactions that use coins but transactions that return coins.

If you go to the grocery store and buy 8 or 12 items then the distribution of change will actually be pretty uniform.

Just a single item sold by weight will do it. But also so many prices like $3.19 or $2.59 will mix up the second-to-last digit of your total, and your total item count mixes up the last digit.

Not to mention the items which get sales tax applied further scramble any pattern that might have existed previously.

Laundromats seem like more of the exception then the rule. Besides vending machines, I can't think of any other service priced evenly in coins -- especially after sales tax.