While I enjoy fantasy art and sometimes use it for inspiration I think the big dog - rabbit? - ears just look a bit silly. Especially because, as
@Lanefan pointed out, every other race is getting bigger and bigger ears.
Are they more aerodynamic? A signal for sexual selection like peacocks? I mean, they're too big to be functional or practical. At this point it's kind of like antlers on deer showing off how strong they are in order to attract potential mates? Do they have ear batting contests?
I mean, seriously. Where does it end?