I've been to many on the list and think that rudeness many times comes from cultural differences. E.g. In China I find people staring at me at first it made me uncomfortable, now I turn it into an opportunity to interact.

I've come to the conclusion that to them I look like Colonel Sanders of KFC fame. :-)

If you try to interact, try to learn a bit of the language and try to approach people with an open attitude the "rudeness" goes away. Or it just doesn't matter.