Make an option to disable "friends of friends" from joining your lobbies

I love the open lobbies feature. It allows me to just sit and wait and see if any of my friends wants to join my ragtag couple of friends that are on with me. What I do not like, however, is when the friends of THOSE friends join my lobby. Unfortunately, everyone has those few "bad apples" in their friends list, whether it be for personal reasons or just shear laziness of not wanting to remove them.... But its annoying when I get random people that join the lobby that I don't know at all, and when they start being an ass I'm not one of those people who feels good about instantly kicking someone.... And yeah sure, I could disable open lobbies, but its not my friends that are generally the problem, its their friends and the friends of those friends that are quite.... questionable sometimes. I just feel like this would be a decent feature.