In my state there are two things with the must inform
you must ask for informed consent before you enter someones home (pursuant to statue I must inform you that I am presently armed, may I enter...)
and inform LE when you have 'official contact' with them...
so yeah, a few friends know I carry, and I know a few of them do too.
Other, well, you have to decide what is more important, and yeah, I leave it in the car rather than have that conversation
FUNNY is the number who are actively supportive.