"I like basketball, if that's what your asking me."
These young stars never get a proper education. They're withdrawn to pursue stardom with the understanding that they'll continue to be privately educated, or some such ********. They of course never actually spend any significant amount of time with any sort of tutor/instructor and they waste any intellectual potential they might have had.
16 years old and you don't know what someone means when they use the word German?! I don't really know if it can be blamed on a lack of education in this scenario. Certainly Justin has come across the word at some point, or would have picked up some sort of information about Germans in Germany speaking German and would have been compelled to investigate the concept further, but perhaps not.