What’s the lure? For me, it is the nature of crossbreeds and hybrids. D&D has it’s examples of old; from the half-orc, half-elf, half-ogre, ogrillon, alu-demon/cambion, and more. “Ecology of the Greenhag” from DRAGON #125 comes to mind, where greenhags are described as the daughters of night hags and the annis is the daughter of a greenhag.
Along comes 3e with half-fiends, half-celestials, half-elementals, half-dragons, half-fey, half-trolls, and more. Reality is filled with unusual crossbreeds; camas (camel/llama), zorses (zebra/horse), ligers/tigons, and wolphins (bottlenose dolphin/false killer whale) to name a few. Why should a fantasy realm be any different?