For identification if they get lost, helps to get them back home. All my rescues were “chipped” when they left the shelter. And you can have any pet “chipped” on your own.
My yellow Lab rescue has this thing he does—when I sit down to eat he will go to the door and whine to be let out, when I get up to let him out he rushes back to the table to try to get my food. It worked only once and he got himself a plate of spaghetti, but he keeps trying—he somehow understands a diversion tactic.
Here in the States we like to label everything—LOL