Perhaps people learn French, Latin, and German because they want to. Who are you to say what they may or may not choose to learn? A diversity of education and knowledge is a good thing for a culture, and if it was not, people would still be justified in learning what they want to learn.
Besides, that we have a sizable population that either has not yet learned English or has chosen not to does not create an obligation in others to learn their language. Are you certain it's more important to enable a sub-community that has not embraced the dominant language of the country, rather than be able to experience the thoughts of the ancients in their own Latin? To extend your argument, I live in an area with a large Hmong population that has not fully embraced English; should the schools here abandon education in all languages but English and Hmong?