On the topic of people learning (or not learning) the native language of a country they are visiting, I'm a firm believe in knowing two important phrases wherever you're going:
1. "Thank you." Generally speaking, a very simple phrase to learn. Though I once asked a Korean friend how to say thank you in Korean, and he responded with what seemed to be a complicated and surprisingly long answer. But it's easy in German, French, Spanish, Chinese, and Japanese, among, I assume, many other languages.
2. "Do you speak English?" In some places (e.g., China), this phrase will be redundant, as the natives that speak English will likely identify you as American -- or not very many of them speak English, which is tough for everybody. My wife and I took our honeymoon in Montreal and got a lot of use out of this phrase, as I think most people appreciate the effort involved in approaching them in their preferred language.
So that's my personal entry for the official CPA Guide to World Travel.