I am a very light sleeper. A cat jumped on my truck and the shaking woke me up.
It comes from many nights on call where a slight noise even would wake me up. I pop awake when people walk by talking. One of the reasons that I parked in the back.
I have never worried. I have slept with the screens in the window even. Never ever thought about strapping the doors together. But not a problem to get out quick. Ever hear of pocket knives?