To add to that list, in many places zip-codes just don't matter, I think they're mostly a US/UK thing. I'm from Eastern Europe and I found myself many, many times googling for my address's zip-code when filling-in online forms because I have never known it by heart (and before the advent of the Internet I very rarely used it).
In Germany they're needed as well. And in my home town there's actually two streets with the same name in very different parts of the city, distinguishable by postcode.
Furthermore, they ease automatic sorting and sure, once your mail reaches your local postperson, they know the neighborhood and names and addresses, but that doesn't mean postcodes don't serve a purpose.
Fun fact: several Central European countries are being quite often (wrongly) described as East European. So while at it, in that part of Eastern-ish Europe where I'm from the ZIP codes do matter :)
