Re: ...advising customers to keep their phone batteries charged...
"It's more worrying that water damage would get them in a real disaster situation."
The disaster will have to get all three of our Sonys, then. The first one was bought to replace a waterproof Sonim which paid several visits to deep puddles. And they have a "Stamina" mode.
In the UK (and the US based on Apple sales) water resistance and long battery life don't seem to be perceived as important.