Actually, I kinda am from non-english speaking country myself and use a couple more languages that are not English. Funny enough, Google localization is one thing that made me switch to DuckDuckGo. Somehow, Google thinks if my IP is from Latvia — it has to speak Latvian to me (which I'm admittedly a bit less comfortable with than English), if it's from Netherlands — it has to speak Dutch (which I don't speak at all). And (aside from manually adding bizzare GET-arguments into url) it doesn't even allow me to chose language myself. One evening it asked me to confirm some user-agreement in Latvian before I'm allowed to continue using search, I got annoyed and said "That's enough".

Yes, in some languages Google search is sometimes superior, but the difference isn't huge and I always can type "!g something" into DuckDuckGo if I need to (and I don't have to confirm any user agreements in that case).

In fact, what still makes me use Google search sometimes isn't localization or some clever heuristic features like flight search, but "search by image" feature. I don't know any other engine that would do that nearly as good as Google. TinEye is left far behind, unfortunately.