I think this thread is strong enough to stand on it's own, but here's some related topic threads for you viewing, to give some insight.
Metareferences and intertextuality ~by B88
Lewis Carroll's influence on Tolkien ~by littlemanpoet
Mythologies in Tolkien ~by Iaurhirwen
These are just a few I went searching for, I know there are many more.
To answer the question though, it does make you wonder. I believe they actually have college classes now fully devoted to studying Tolkien and his works.