They were a family from, I presume, the far east, on holiday in this fine city, and enjoying the cultural highs of the British Museum and Premier League football. It was cold last night and this morning so for the fellow to pick up a practical momento of his stay is fair enough, I think.
Matthew 7:1 though, surely? "Or if he asks for a fish, will give him a serpent?" doesn't quite seem to chime here.