Well, Tolkien says the Cirth is for inscriptions and the Tengwar is obviously designed for calligraphy with pen and ink... Elves were beings of beauty and grace... and part of poetics is the physical appearance of something written... They would appreciate a poem not only for its sonics, but for its appearance on the page... not to mention that they must have had whole scriptoria for illuminated manuscripts... Think of Jappanese or Chinese calligraphy not to mention our own Western manuscripts...