In real life a large number of corporations (and developers) have their computers configured with English as this is the main language of the coorporation and makes IT-support much easier. (we don't even need to talk about how badly botched many language translations are).
These users will still want Google to return results in their native language.
There is a much much larger number of users like this than travellers from USA.
One thing that bothers me a lot with US websites is that they always assume English language means 12-hour clock.
Apple has learned the above over time: it is much easier today to get a Mac running with English and 24-hour clocks.