Do you talk to your team members for 8 hours a day? I don't. I may catch up with them in the morning for something, perhaps go out for a coffee, or do some pairing when debugging etc but 80-90% of the time I am working on something alone. I can work far more efficiently in a private space. I cannot concentrate when I know that there are people around me all day who can interrupt me or distract me at any point in time without warning.
Of course, I once mentioned this on HN and someone replied that the need to communicate readily with my fellow programmers is a sign that our code base isn't well-documented. I thought that was pretty funny.