I travel to the US regularly, trying to use a foreign credit card there (especially to buy gas - what is my zip code?) is a real pain - unlike the rest of the western world the US is far from being able to go cashless
That's a good thing. As people are learning in other countries like Sweden.
Canadians can use the first 3 of their postal code.
It was in Florida where I ran into the problem... Definitely no sign where I was :)