MaryWestmacott running to get dc is a very understandable reaction but not a helpful one! This sounds a bit weird but based on how people who are tasked with evacuation in the event of a disaster work, it makes sense.
OK, the worst happens, there's a fire, sinking ship or whatever. Security and people with responsibility for evacuation will have a clear plan based on the number of people in the room, evacuees with special needs (there is usually a personalised plan for these people), available exits and logical actions (don't go towards places where a fire is likely to break out...I once worked in a building where the muster point in the event of a bomb threat was in front of a plate glass window! We got that changed). A deluge of wailing parents looking for their dc actually fucks everything up and makes them less safe, not more.
An example from my previous life as a security guard. I had to evacuate 200 people because a fire had broken out. It was a proper fire, not an alert. Most people could smell the smoke and we got them out in an orderly fashion - except for one bloke. He charged through the flow of people towards the fire because he'd left his coat in there.
Evacuating 200 people isn't easy at the best of times and it's worse when you are trying to control the flow of people, you're worried about a spreading fire and some nutter is yammering in your face about his super important coat. At that point, if I was evacuating his dc, they would have been safe like everyone else. My job as security was to get people out of the danger zone quickly and safely. It would be the same if he was yelling where are my tiny babies instead of where is my designer coat, he was actually endangering everyone else.
Trust security, we're trained for this shit. Running towards us yelling "WHERE HAVE YOU PUT JEMIMA AND TARQUIN" in the middle of a disaster makes everything worse. And doesn't particularly help Jemima and Tarquin.