what is up with....

... people at work who carry on private mobile phone convos in the public hallway because the call is so private that they cannot take the call at their desk, yet they venture with this privacy into the public hallway, which is quite obviously the height of not private, and when you walk by them in the hallway, they give you an evil this is a private phone call stare, and you want to smack them upside the head and say - you are in a public hallway, ya doofus!