bunkrest... Please tell me you are joking......
I'm sorry, I may have mis-understood your post.
Isn't it obvious. As somone who has received numerous fire training packages at different work premises, alerting those around you that there is a fire is the number one priority and shouting is a quick method of doing so!
Why should this be any different on a plane? It's the cabin crews primary responsibilty to hear this and take appropriate action, including reducing any "panic" that might ensue.
Please tell us that you are joking???