 Batman did this more out of habit, and Barbara did it as a flirting sort of way to annoy Dick.The police department who discover the Batcave in the beginning of the episode call Robin as 'Red Robin', a reference to "Kingdom Come", and they theorize that Bruce Wayne was Red Robin (with his father as Batman and his mother as Batwoman).In the "Krypto the Superdog" episode, "Bathound and the Robin", a literal robin called Robbie is saved by Ace the Bathound and wants to be Ace's sidekick, much to the dismay of Ace.