I can just see the scene! Bright sunlight, and young people laughing (the poor goldfish made me grin), and Lily making a case for finding happiness even in the midst of war. But it's interesting to see this from Mad-Eye's perspective, as someone who's seen enough bad things to be perpetually suspicious (and the constant physical discomfort of the false leg and the magical eye can't help).

But that's chilling foreshadowing, about always keeping wands in hand, because that was just what James didn't manage to do in the end. (Not that a wand would necessarily have helped against an immortal Voldemort, but, still.)