In fairness to the GP, I've never heard anyone call it a "game" in the > 20 years since leaving school (and even at school people only said it in reference to a friendly kick-about at break time). In fact you'll find a great many football fans get quite offended if you call their much loved sport "a game" as they think it belittles the importance of the matches.

So I'm very surprised to read a fellow British-man advocate the usage of the term "game" in reference to football.