I live in Erie PA and just about every day I get Canadian coins as change all over the city. We just use them as U.S. currency, usually it’s a dime or quarter mixed up with the coins, most people don’t notice. When I receive Canadian coins I set them aside and having been doing so for 20 years just to see how much I could accumulate, I have over $500.00 of Canadian coins just from saving the few I get as change.
Was in Victoria, BC just a week ago…every time I pulled out American currency it was accepted…and I got change in Canadian, taking the exchange rate into account (none of that Montreal shadiness going on 
) In fact lots of clerks seemed to know the exchange rate off the top of their heads.
I’ve noticed that back home in Seattle there is considerably greater reluctance to take Canadian cash. And no-one knows the exchange rate.
Okay, we all knew I would show up with a Texan angle.
Never see Canadian currency around here (small Central Texas town). When I lived near the Mexican border, most major retailers would accept both US$ and Mexican pesos. In fact, the registers would ring up the total both ways. The exchange rate, however, is so lopsided that I can’t imagine anyone simply taking pesos as dollars. If you paid with pesos, you were expected to pay the peso total.
Funny thing, though. If you crossed into Mexico, the shop-keepers were always delighted to see dollars. They rarely dealt in pesos, from what I saw.
Well, I grew up in Montana, and it was very common to see Canadian coins around town. When I worked at a little gas station just a bit south of the Canadian border (little hamlet called Choteau) it was common for Canadians to pay with Canadian currency.
Several of the ladies knew the conversion of their heads. Nobody kicked when we made them pay more in Canadian, it was kind of expected.
Now that I’m down here in California, I still see the occasional coin. Not many, but a few.
A friend several years ago told me of his weekends in Europe when he was in the Army… I guess many countries had coins that would work in other countries vending machines… the one that he talked of most was some polish coins (dirt cheap) that fit into the cigarette machines.
Retailers here accept US coins at face value, bills at a crappy exchange rate. You’re always much better off hitting the ATM first.
I noticed in a recent trip to SLC, I accidentally passed some Canadian quarters. The new state quarters confuse things and make my funny money less noticeable.
In 1977 I moved from Montreal to Los Angeles. I was in tenth grade, so within a few weeks I had to buy some supplies from the student store at my new high school. I paid with a bunch of coins including one Canadian penny. The sales clerk instantly spotted it and told me it was not acceptable.
Ed