Several have asked us why we are there learning French. At first I just said 'why not?,' being flippant because I couldn't think of what to say. Here are some of the reasons: 1) I simply like learning new things. I find a pure pleasure in the process of learning and, moreover, opportunities to learn get fewer as one gets older. 2) I started to learn French, so I'd like to complete it, or at least, get as far as I can go. 3)It's too easy to live in America and to never think of the rest of the world. As I learn another language, I learn about another culture. Language acts like a key so I can learn even more about that culture. 4) It's easier to have a civilized lunch in a French cafe, if one speaks at least some French.
I also remember the 'graduation ceremony' at the intensive course the Cranky Old Geezer and I took at Dartmouth some years ago. There were hundreds of students there studying many different languages and we all walked in a line, led by the professors attired in academic robes with colorful hats (viking helmuts, beanies with whirlagigs, court jesters hats etc.) and as we walked all over the town of Hanover we all chanted "Hey Hey, Ho Ho, Monolingualism's got to go. Hey Hey, Ho Ho Monolingualism's etc."
Not a complete answer, but part of one.