Last night was the final class of the "Japanese Beginning I" course I've been taking. I enjoyed learning another new language and will sign up for the next class. After class, I stopped by Half Price Books and found they had a copy of Japanese for Everyone, which looked like a pretty good book. I didn't buy it last night, but after I read the reviews on Amazon at home I figured it would be a good purchase. So after getting my picture taken I went to pick up the book. After I paid for it, the cashier said 「ありがとう ございました」 [arigatou gozaimashita]. I understood but I wasn't really expecting that, so I didn't manage to say anything coherent in return. I guess the correct response would have been to say the same thing back (it means "thank you very much"). It seems that you can't go wrong by thanking the other person, or excusing yourself, too much in Japanese.
I just realized after writing the above that I had two good customer service experiences over lunch today. It's little things like that, that make me want to do business with those companies again.