Celebrim
Legend
After all, if hippogriffs, for example, were naturally occurring animals that could be bred, why wouldn't every kingdom worth the name have hippogriff stables? After all, you're not talking huge investments compared to the rewards of having flying mounts.
I find it odd that you would complain about Hippogriffs being used as steeds by anyone that could capture one, since the Hippogriff of myth was bred from a Griffin and Mare precisely for that purpose. Hippogriffs almost exclusively appear in myth as steeds for mighty heroes of valor. That's there role in myth regardless of what you think of their biology.
So why don't you have orders of knights using hippogriffs for steeds? Every kingdom worth its name does have hippogriff stables. Alcegraff, the Griffon paragon, wouldn't have it any other way. The whole point in him stooping and humbling himself by mating with a mare was so that mortals might have a steed suitable for battle with fell beasts. Hippogriffs are for war. That's their purpose. That's the thing they live for. Wild and untamed hippogriffs are something of an abberation, and usually the result of some sort of folly.
I believe that monsters should suit their myth. The central question is sort of, "If these myths were real, what would it be like?" Hense, I despise when dragons are used in some role other than as hoarders and destroyers. The great problem I find with how monsters are used, isn't that they are treated as biological, but that they are anthropomorphized. What I really despise seeing in a story or setting is the monster treated as basically a human in an unusual shape or with unusual powers, but with human desires, human motives, human methods, and human modes of behavior. That I think is the real creeping problem in D&D and modern fantasy in general. It's not merely that the monster is treated as mundane because myth assumes that monsters are mundane, albiet just over the hill there along with other fantastic beasts like giraffes, hippopotomi, and panthers. The problem is that monsters are assumed to be merely human. This is a degree of familiarity and normality that far exceeds them being merely mundane. This is the real failure of imagination.