A few things: there are cell phones everywhere these days, so even if an individual doesn’t have one, there’s no reason why they couldn’t ask to borrow someone’s phone for an emergency situation - especially when there’s a missing child. Time is of essence.
Also, it often seems like they’re worried about what they might accidentally say to the 911 operator and they know that call is recorded, so it seems like they’re trying to hide something.
It would be totally understandable if someone was, say, out hiking in the mountains and cell coverage sucked, you’d do the next obvious thing and go to the nearest police station to report something, but not in the middle of a city where cell phones and cell phone coverage are available everywhere.
