I've noticed there are two kinds of people in this world-
1) those that, when on the phone, prefer to retreat to a private/quiet area in order to carry on the conversation (for two reasons- privacy and consideration of others in the vacinity not on the phone);
and 2) those that walk over to where others are sitting (on the computer, or, perhaps, reading) and carry out the conversation as if, for some reason, the third non-phone-party wished to hear the person's end of the conversation.

Just an observation.