And it's worth noting that there are competing forces at play in the design of offices, and choices aren't always made with productivity as the primary concern.
Many software shops are desperate to mirror the popular notion of how these places operate: loud, boisterous bullpen type arrangements, whiteboards all over with various contrived things on them, street lights flashing the current iteration progress, desks littered with crazy toys and blimps and toy guns, and various nerdly hijinx. It is, in every way, cargo culting, putting the image of how it should work against the actual of how it works.
It looks like what many outsiders think a software shop should look like, all those geniuses doing their genius thing.
Impress investors. Impress potential hires. To the latter most will say "oh no! That wouldn't impress me", but the truth is that real work in this field occurs in the most boring looking way possible, so we all like to imagine that a vibrant office will be an amazing new experience. But in the end we're still wrangling code all day.