I love reading happy-ending stories of lost or stolen cats being reunited with their human and this happens more and more often now with the advent of the chip.
I’m rather embarrassed to admit that I 
actually have my first “chipped” cat. Olivia came with a chip and, of course, I followed through and filled out the paperwork so IF she were to become lost there’s a much greater chance that we would be reunited.
Things happen. There are disasters where animals become separated from their families; indoor cats find a way outside and become frightened, disoriented, and lost; someone might walk off with a cute dog or cat they see even in a fenced yard… Earlier 
this year I saw pet spa employees chasing after an escaped dog. Pets can become lost while traveling with their humans.
Evidently microchip technology was first used in fisheries to keep track of the movement of fish. It is currently being used with wild animals, livestock, and our pets to monitor movement and with household pets, to prove ownership.
If you love a happy-ending story like I do, you might find this site uplifting. It highlights true stories of pets being reunited with their people because of that tiny rice-size microchip. https://www.pettrac.co.uk/microchip-database/pet-microchip-reunification-stories/
