I'm sure they do. Not that I ever want to go through it but if an emergency occurred at say around lunch time on a nice day when basically no one is in their cabin it would be quite a commotion if people had to go to their cabin to get a life jacket. People running everywhere, being held up by scooters, walking frames being shattered, people insisting on getting an elevator despite having to go one set of stairs, people trying to get the App to work to see where their companions are, etc. It would be pandemonium.