Make of it what you will, but on the French AZERTY keyboard, the Euro is an option for the Dollar.
And there is a slight difference in the position of the Euro sign in QWERTY keyboard layouts.
In US Qwerty layout, press Option+Shift and type 2:
⌥+⇧+2 = €
In British English Qwerty, just press Option and type 2:
⌥+2 = €
In AZERTY (France) layout, the Euro sign is on the same key as the Dollar sign on the right of the top letter row. Press Option and type Dollar:
⌥+$ = €
On British Qwerty, the dollar is Shift+4 and the pound is Shift+3. However, on US Qwerty, there is no pound at Shift+3. You have to type Option+3.
Why this confusion? Originally, keyboard layouts were developed for typewriters in 1880s and computer keyboards simply adopted the already existing layouts adding new signs as options.