Why do home addresses in Pakistan start with the House Number and end with the City?
Pakistan’s postal service, i.e. Pakistan Post takes its roots from the Indian Postal System, which in turn took its roots from the British Postal System (or the Royal Mail).
Pakistan is a member of the UPU (Universal Postal Union) and the framework that we had at the time of inception (circa 1947) remains in use today. If you will ask why don’t we use the UK Postal Code, well that was implemented in 1959 so we did not follow it (or rather it was not something we inherited at the time).