Kinda like every EuroZone country is using a foreign currency over whose value they have no control.
yitbos
Except for Germany, which, sets the terms for the entire Euro zone. Other countries tolerate this because German cash is now keeping the Euro afloat, while the cost for Germany is offset by being able to buy and sell throughout the Eurozone on favorable terms. And, although no longer issued, the German mark is still a valid currency.