When I first picked up the books, many years ago, I read over everything and looked into the languages that Tolkien created. It held my interest for a while as I would interpret the names of people and places in the books, hoping to glean any additional information that I could. Now, there's barely time to read the books..
Anyway, in regards to your question, you might not want to bother wasting time trying to defend your choice as most people will see it as odd and as a complete waste of time - but so what? It's your time to 'waste' and as long as you are balancing it with other commitments (i.e. "I decided to quit my job in order study Elvish 24/7..."
), where's the issue?
I find it odd that on a beautiful day people (many in my own extended family) will sit on the couch for hours screaming at men playing with a ball on the television. But I guess there's some justifiably good noble important reason for this activity that I must be missing.
Good luck with your studies, as you never know where they will lead you.