A different look -- the data center is an economic and aesthetic paradigm that just happens to be a physical location.
Computers and telecommunications equipment at the industrial scale need a number of utility services provided and it is cheaper to mass the equipment together and deliver these to one location instead of many. The information processing equipment of an enterprise requires delivery of the following services: electricity, refrigeration and climate control, data traffic, operations staff, monitoring, repair and maintenance staff, physical security, storage/disk, fire detection and suppression, and air purity/filtration. Not all of these (monitoring, SAN connection, etc.) require proximity, but there is an economy in sharing particularly when you consider the need for fail-safe redundancy and rapid access across the services.
Further, (and while this may sound lame, it plays a critical role in corporate decision making) a big room full of row upon row of racked computers is a very nice tour stop for the CFO. This is also why network operations centers are often attractive, inefficient showcases as well (and may be located with the data center).
Data center culture -- the darker side of IT? …Nah
Over the years, I've worked and played in a number of data centers and talked to people who lived in several others. Some facilities were small (wiring closet would have been a better name) and some were large (39,000 square feet -- all for one enterprise). But pretty universally, the professional people who kept the data center operating were treated poorly. These people range from tape monkeys to electrical engineers, repair techs and misplaced DBAs. Like any other cross section these people wildly range in their level of competence and degree of social skill. But a sysadmin working in a data center earns less money and respect than the same person would (and does) if (and when) they work in an office.
Also pretty universally, these data center staff engaged in what might be called by management, egregious misconduct in the pursuit of fun and humor, typically with little concern for the consequences -- to either themselves or the enterprise. These people occasionally display amazing creativity in finding ways to pass time in a manner disrespectful of their employer.