>Because you alter things outside of your perimeter.
Indeed, but you need a permit for a lot of things contained within your property too. Technically, I need a permit to change my front door. Kinda silly, mostly ignored by people, which is probably a worse outcome.
Homes can have neighboring properties and non-owner occupants and there are third-party fire risk concerns with both. It is not good if people build homes which are at risk of spreading fire to neighboring properties, or at risk of harming occupants in case of a fire.
Building codes are a big reason we don't have nearly as many events called "the great fire of [city]" in the 21st century.
Indeed, but you need a permit for a lot of things contained within your property too. Technically, I need a permit to change my front door. Kinda silly, mostly ignored by people, which is probably a worse outcome.