So, no game is perfect. Obvious fact.
But "sleepy town" version is plausible. Another one: all citizens feel it's safe because of Boone watching the surroundings. As for the old hag: she's to senile and arrogant to figure out that thing.
Why anyone trust the Courier in "One For My Baby" quest?
IRL would you leave your house in the middle of the night if someone invites you to see "something interesting" outdoors ?