What did you expect it to show you? It seems like a decent result to me. Possibly google doesn't know any sushi restaurants near you in Warsaw.

pointless zip-code form.

It's not pointless if you are looking for a place to eat sushi. You're performing a hypothetical search for something that you aren't actually looking for and then calling the results pointless.

Google can pinpoint your location very accurately, and they are usually quite agressive in promoting local results (including for tech queries, which is a pretty bad idea), yet they ask people in Poland: "In which US city are you ?".

I find that quite funny, to be honest.

In Australia get the same search results as you, but there's no 'local search' section. I'm logged into google in FF

In chrome, with no login, I get a different set of results, including some local restaurants. Curious.