There's a huge success story in machined buildings - Butler Buildings.[1] They have about 100 standard steel parts, from which industrial and farm buildings can easily be constructed. Rural America has millions of their buildings, from small sheds to large factories. They offer wall and roof sections with and without insulation. (Their site promotes the fancier options for schools, malls, and churches, but the volume is in the plain metal ones.)

There are competing systems, such as Behlen.[2] ("Good iron. GREAT experience"). All these systems bolt together on site, usually mounted to a concrete slab. Such buildings are dull, boring, weathertight, easy to erect, and durable. They're rarely seen in cities, so many people don't know about them. But get thirty miles outside a big city and they're everywhere.

[1] http://butlermfg.com/en/butler_systems_details [2] http://behlenbuildingsystems.com/resources/photo-gallery/agr...