Taking off your hat. . .

is really a thing of the past.

Hat check girl, New Years Eve, 1942.

It's interesting to note the extent to which this is true.

When I was a kid, we were taught to take our hats off when we came indoors.  If you didn't do that, sooner or later some adult would tell you to take your hat off.  As I don't like wearing hats indoors, even though I wear a hat all the time when outdoors, I did, and still do, that automatically, but the impression of this is strong enough that I still recall being complemented by adult as a kid for doing that on one occasion.

As noted, I still take my hat off every time I come indoors, nearly without fail.  Only recently have I taken up putting on a cap just before I go outdoors, and I feel self conscious about that.

Adding to that, perhaps, when I was a National Guardsmen you never wore a hat indoors, except for the limited exception of being in formation in a drill hall or if you were under arms.  Otherwise, the hat was off.  If you forgot that, somebody would give you the inevitable "Is your head cold?", reminding you to remove your hat.

Of course, when hats, as opposed to caps, were more common, there was very real reason for taking your hat off.

There still is, but caps are less obstructive so there's less of a reason now.

It still strikes me as something that a person should do, however.

Be that as it may, many people simply do not.  I see piles of men wearing ball caps in doors now, all the time. I don't think its regarded as rude any longer.