I think it did a couple of months back (thats another thing I hate about Americans, they always say stuff like 'a couple months'),
...
I have been know to play the American stereotype in the past so perhaps you're right.
"A couple months" is proper English btw. You're saying a quantity (a couple) and a measurement (months).
When you say "a couple of months" then you're saying a quantity ("A" or a single unit) followed by a measurement (couple of months).
In other words you say 1x2 and we say 2x1.
Other similar phrases:
A few years
A few of years
Many months
Many of months
To put a serious answer to the OP though: Americans were born and raised knowing that the English use the Pound. You guys then joined the EU which uses the Euro. This made headlines.
The fact that the UK (and I think Denmark) skipped the Euro was a big deal for the respective countries and the EU. It was not a big deal outside the EU though and never really made headlines over here.
That left most Americans with the impression that you use the Euro.
Those of us that travel know otherwise. You have to also realize that traveling outside one's own country isn't as widespread in America as it is elsewhere. Most Americans will hit Canada, Mexico, and some Carribean nations (our equivalent of like Palma, Spain) for vacation. Most other travel requires going over the ponds and it's just not affordable.