Lament for the Elves

[Firefoot]

Yes, I'd say it came about because of the movies. In the books I cannot imagine Dwarves using these kinds of insults. Also, here is an excerpt from BoLT 2 about what Tolkien thought about this stuff (always been one of my favorites because it is so against the movie portrayal )

Long afterwards my father would write, in wrathful comment on a 'pretty' or 'ladylike' pictorial rendering of Legolas:
He was tall as a young tree, lithe, immensely strong, able swiftly to draw a great war-bow and shoot down a Nazgûl, endowed with the tremendous vitality of Elvish bodies, so hard and resistant to hurt that he went only in light shoes over rock or through snow, the most tireless of the Fellowship.

It would seem, being that Tolkien died before the movies came out, that this "ladylike" idea of Elves has been around for a long time, though JRRT never meant for them to be seen this way.