The great Robert Krulwich:
Until cars became the dominant mode of personal transport, there was no architectural reason to take your hat off between home and office. With Dwight Eisenhower’s interstate highway system came cars, and cars made hats inconvenient, and for the first time men, crunched by the low ceilings in their automobiles, experimented with hat-removal, and got to like it.
And ruined his father’s business in the process.