Open office plans has been a subject of significant controversy recently, with everyone and his brother pointing out that the quiet craft of software development clashes horribly with the loud, communal, extroverted environment of open office plans. So the question then becomes: who benefits from this arrangement?
Venkatesh Roy has this thesis-- he calls it the Gervais Theory-- that all modern office hierarchies have three kinds of people: the losers, the clueless, and the psychopaths. Extroverted and manipulative, pychopaths form companies and temporary alliances as they claw their way up the corporate and financial hierarchies; their lives are wrapped up in playing this game. Losers don't play the corporate game at all; they knowingly enter into arrangements with psychopaths to do the work and go home to their "real lives." The clueless are mostly middle management: they believe in the company, but play by the rules, believing they'll be rewarded for their loyalty with greater rewards. Eventually, the company is filled by successive layers of middle management until it becomes a hollow shell, at which point the psychopaths cash out; the losers, who knew this was coming, transfer their transferrable skills elsewhere; the clueless are left wondering what the hell just happened. The psychopaths go on to form a new company; lather, rinse, repeat.
Software development is so hot right now that skilled developers can just up and leave. They can find work elsewhere. If they're bored and unrewarded, they will find work elsewhere. Psychopaths need to keep a closer eye on their software developers than on other productive roles, like in manufacturing, refinery, delivery, and so on.
The open bay permits that. It gives the psychopaths in the room a horizon they can scan for trouble. It gives them an intelligence edge they wouldn't have if developers were all in their own little rooms.
Open office bays are a mechanism for controlling restless developers.