I'm wondering whether all those who advocate taking a hardline with mrChelseababy would be similarly inhospitable towards their DCs' friends.
My DD1 had a habit of collecting people and at various times we had a group of young Swedes staying, some Americans, and most notably a Japanese family who spoke not one word of English. As gaga says, you get a great deal from these experiences.
I was amused and flattered rather than annoyed when one of DD's vaguer, more disorganised friends rang us from the airport one day and said 'Er it's Graham here, could someone come and pick me up?' and proceeded to stay for dinner and sleep on the sitting room floor.