I work at a convenience store. We have a penny jar. Except about four months ago people starting leaving dimes, nickels and quarters. It was not a gradual change, people hardly ever left more than pennies. And it is not just one or two people.
My take is that nothing less than a dollar bill is worth much anymore. Part of this is could be the issue of cash vs card, but my uneven sample says that ratio is not really changing.
And what can you buy for $0.25? Nothing. $0.50? Nothing. Not a cheap drink, not a cup of coffee. For a dollar? Still nothing.