I did a paper on this topic. It was a decade ago, but the research is still valid.
Sorry for the lack of online sites. At the time, I was at the library reading microfilm and microfiche, before the Net became popular. Please forgive me if I sound overly passionate. It’s not my intention to push this into Great Debates.
Disclaimer: I prefer a one dollar coin over a bill, but I’m not holding my breath. I like dollar coins from other counties. The Euro coin design is a good compromise between unity and diversity, and the bi-colored Canadian Toonies look cool.
The single most important reason why the U.S. will not embrace a one dollar coin is that we’re still printing paper money. Case studies for other counties showed that the government had to cease dollar bills for the public to adopt coins. Until we stop printing dollar bills, people will not feel comfortable using dollar coins, no matter how pretty, shiny, durable, or cost effective they are. (A coin costs three times as much to make as a bill, but a coin will last 30 years versus 22 months for a bill. Bills last even shorter if you accidentally leave them in with your laundry.)
Other less significant, but important reasons, simply because the public can relate to them more:
We’re not upgrading all automated machines I’m talking about all machines that normally accept one dollar bills: vending machines, ATMs, parking meters (or at least the ones at fancy garages), copying machines, arcade machines, change machines (for quarters), public transportation turnstiles, and so forth. All it takes is one instance where your dollar coin is not accepted at a machine (and there’s no one to help you) and you’ll have a negative impression etched in your brain. For instance, out of curiousity, I put a dollar coin into a vending machine; the machine registered it as a quarter.
We’re not upgrading all merchant or service machines. In this case, I’m talking about all cash registers. Can’t tell you how many times a storekeeper or grocery checkout person will stare at the cash register’s money tray to figure out where my lone dollar coin will go.
We’re not upgrading all personnel. We’re not training people on how to deal with dollar coins. How many entry-level people working at McDonald’s have seen a dollar coin or know that several kinds exist? As the OP noted, we have the silver-colored Susan B. Anthony, the golden-colored Sacagawea, and the new Presidential ones. In contrast, everyone can instantly recognize a dollar bill. We’re used to the idea that coins are “chump change”. To a waiter, a handful of dollar coins doesn’t look like much compared to its equivalent in bills. This is a perception that needs time to change, and the public is too impatient to care.
Humans can be very creative and adaptable* when necessary. I find it illogical to think that Amercians are somehow stupider just because the rest of the world’s civilized nations are using dollar coins (and the metric system…although Brazil may still be a holdout). The thing is, unless we make it necessary to use coins by eliminating paper, people will not see the immediate benefit of cusing coins.
*When I was in Canada, I noticed that my friend carries dollar coins in a 35mm film canister. (For young’uns who have no idea what Grandpa 2P8 is talking about, see here.) In the States, some transit operators wear coin dispenser belts .
That’s my $2 coins worth. I’ll get off my soapbox now.