Pet owners do not do this...microchip yes
If yous pup gets stolen you have a bigger chance of getting it back with a microchip as the chip numbers go into a national database and vets and shelters have guns. Not all have the tools but if your dog was taken into a shelter 2 towns over from yours the vet wouldn't have a clue where to find who the numbers belong to.
I also think the numbers are not very nice looking on a dog...reminds me of the Nazi's
