I was thinking the same thing. It's not fairly common for anybody to just casually ask me for my zip code unless they're going to mail something to my house, or are trying to figure out an estimated distance for a trip. Outside of that I don't see people casually asking for your zip code.
Or are trying to tell you what the weather is going to be this week.
You could typically type in a city name and that would give you a good enough idea. I guess that could be, but I've never had anyone ask me for my zip code for that.