Why weren't Batman and Robin's origins depicted on this show?

Was it simply because it was way, way too intense and dark for the type of show they were attempting to make? I know that Bruce Wayne in the pilot, does make a passing reference to the fact that his parents were murdered. But I don't recall them ever going into explicit detail of what actually happened.

I always point to the late era Super Friends episode, "The Fear" from 1985 as proof that Adam West could've played a more emotionally tormented and conflicted Batman when asked. That episode was actually the first time that the murders of Thomas and Martha Wayne as well as why Bruce chose the bat-motif for his superhero alter ego, were depicted on film or television.

https://www.youtube.com/watch?v=MdeOBa-YyRs