Almost every laundromat bill changer I've used accepts 20s. I always felt very self-conscious getting so much change at once, but maybe it'd be more fun if it had lights and bells on it.
I remember the opposite experience in the USA when I was a child. We needed to make an international call from a payphone. Struggling with it, eventually my dad called the operator, who said the call cost $8 or so, and we needed to put the coins in quickly. We tried several times, but my dad and I were unable to feed in 32 quarters before something on the machine timed out, and spat them all back out.
Interesting. I used some kind of pre-paid international calling card for the handful of times I needed to make international payphone calls. I'm too young to have remembered a time when payphones were in constant use, but I definitely used the payphones at my high school once or twice to call my mom when my cell phone died.
FWIW, $1 coins were (and are) in circulation, but not very common and probably not accepted in payphones. The NYC train and subway ticket machines have dispensed $1 Sacagawea coins as change for as long as I've used them.
