Unless they are in the military, gentlemen do not wear their hats indoors. But whatever floats your boat. Nothing wrong with balding men.
And if one must wear a hat indoors please take the dang thing off at the dinner table. Ugh!
Uh...when I was in the military we had to uncover indoors as well. Under normal circumstances you NEVER wore a cover indoor. Likewise you NEVER EVER went outside without one.