I’ve been on the fence regarding portable back-up power, but there’s lots of “stuff” that we use and carry daily that needs electricity. Many of us take for granted that electricity will always be available - until it isn’t.

I usually keep all my various electronic gear charged, rarely do any of them go below 50% charge, but some of them (cameras) will go from 100% to below 50% quickly and usually far from a wall plug. In those instances, a portable power pack is very useful. Just another opinion.

PS: I’m probably going to get the Anker 20100 mAh Portable Charger. Want/need, don’t know.

Edit:
Want, not need. It’s a convenience and there are other ways to get batteries charged. But out and about with no 12VDC plug let alone a 120VAC wall plug, 20KmAh is nice to have.