I taught English at a small coffee shop in Nara, the last couple times I went to Japan. The name of the coffee shop is Hyde and Seek. The students ranged in age from 25 to 73 but most were in the 40 to 50 year old range. I taught two separate classes, one for beginners, and one for intermediate students.
Because of the age of my students, they were in class to learn. Yeah, much of the class was in Japanese since many of them knew each other and were enjoying the social aspect of the class. Still, when it came time to learn, they were ready with pen, paper, and electronic dictionaries. It was gratifying as a teacher to teach students who wrote everything you said, tape recorded the class, and asked relevant questions.
Their reasons for learning were varied. From those learning English for travel, to others learning for their jobs, and those who simply thought of English as a cool hobby. I continue to keep in contact with the owners of the coffee shop, and many of the students. This was an incredibly rewarding teaching experience.