Except, experimentally it doesn't seem to be true most of the time. This is an entertaining article reporting an experiment testing whether people can recognize the type of building from the exterior design. In short, they can't. I'll leave you to read the details of their experiment (and what it suggests about the sad state of American architecture) and just report the ending:
Other studies have shown that people already "read" buildings to judge the status of people who live or work inside, and to determine if the buildings are in a safe neighborhood, among other things, Nasar said.
"Buildings convey meaning, whether they are meant to or not," Nasar said. "So it makes sense that buildings be designed to indicate their use. But our results suggest it doesn't often happen."