There’s nothing wrong with something being rare. It makes it special. Nobody cares to see someone wearing the Org tabard you can buy from the vendor but people take notice of this tabard because they say to themselves “hey, that guy took the time to farm Scarlet Monastery” or “wow he got lucky!”
It’s the same thing with Invincible. Nobody cares about gryphon recolor #10 but Invincible is rare, he was the mount for the (arguably) the greatest WoW villain and he has his own story.