There are similar phone charging devices that use secondary li-ion cells instead of primary alkaline or lithium, marketed as "emergency use".
In my experience, some of the earliest types in this category (12 years ago?) had LED flashlights and a charging circuit (and an amusing quirk where shining a laser at the status LEDs would trigger the flashlight.)
Individual stories of re-using manufactured but unneeded cells from other products probably account for some of this.
