It's always been a pet peeve of me and da boys to see someone walk a half a block from their car, turn ceremoniously, point theirs hand at their car and lock the doors. This honks the horn and flashes the lights.
Now, when I have to wait in the car for my wife (I'm not allowed to enter a store with womens clothing in it, says I whine too much, JUST BUY IT OKAY) and I hear a horn beep, I honk back and flash my lights.
It's my way of saying "Buddy, if that was my car, I'd lock the doors with the switch on the door". Keep your beep to yourself.
I'm just saying.