Is the plan not for everyone to evacuate if the fire alarm sounds?
In the ideal real world, yes. Unfortunately, people will have that "someone else will sort it out" attitude and may not move at all, which is why there should be staff available ti initiate the emergency evacuation procedures.
It would be an interesting case should a fatal fire occur in one of theses places ...... and a good test of the legislation.
I agree that as a person booking a room, you should be given information on the fire procedures but that doesn't happen.
I asked ithe receptionist at a large hotel I stayed in what the procedure for evacuation was and where the assembly point was. That request was greeted with a very blank look and a referrel to the manager to answer.
Not exactly confidence inspiring.