[Eruanna]

I always thought that the elves had poined ears, long before I read any of Tolkien's other works. I don't really know why, unless it is something that became deeply rooted because of childhood fairy stories.
I think perhaps that our interpretations spring from the romantic traditions of Victorian and Edwardian times. They were obsessed with all thing 'Faerie', paintings, statuary and poetry crammed Victorian ladies' sitting rooms. In turn the Victorian conception of fairies and elves came from the classical Greek tradition of nature spirits; fauns, satyrs and the like which were all depicted with pointed ears.
This is the kind of tradition that Tolkien himself would have known from the nursery. That he moved away from the Victorian ideas (yet retained some) and made something more of his elves we can only be grateful for.