Nerdy nitpick: It might not be quite an "address". In the UK at least the machine readable information (either added during sorting or printed deliberately for a discount rate by bulk senders) indicates a delivery point a place to which this post will be in fact delivered, distinct from an address.
For example my address says Flat 7 of 60 My Street, and a friend lives at Flat 10 of 74 My Street. But my delivery point is a letter box in the front door of my home, whereas his delivery point is just a locked box at street level. Timed locks allow the postman to enter my building despite not having a key, so as to deliver post to my front door, whereas his building doesn't do this.
The company (almost everything in the UK is privatised because Tory ideology says this is a good idea even if it clearly isn't) delivering post owns very detailed maps of where all these delivery points are, because of course it needs its employees to visit all those points to deliver post, whereas it needn't care where in some sense an "address" is other than where the post is to be delivered.
