Maybe they were wearing hats or had long hair covering their ears.
Hm, well, as far as I know, there is only one slight reference to the potential of pointed ears, that being a reference to them being 'leaf shaped.' However, as I've said, judging by the fact that Gandalf himself was taken to be an Elf, I highly doubt Tolkien's own appraisal of Elves was very much like our post-D&D era perception. They were not ethaereal, nor many of the other traits that are currently attributed to Elves.
The sense one might get of the Elves as opposed to say, men, in Tolkien, is maybe the distinction between Vanir and Aesir in Norse myth. But as it is, it is certain that Tolkien's conception of Elves is rather different than that which we are used to. His arrangement of troops before the siege of Gondolin is interesting in this regard as, indeed, are most of the doings of the Noldor (Gnomes, ie. Deep Elves, like Galadriel and Elrond.)