Well (as I said) that's how most credit cards in the world work. And seriously 10€ plus one month's interest (~1,5% of the amount due) is not that horrible should you forget once (knock on wood).

But then, I come from Sweden where you get a nice 60€ fine if you forget to pay the Stockholm congestion charge just one month...

Thanks everyone for the advice and for confirming that the card is legit. I will give it a try and report back!