Also why the HELL were Green Hornet and Kato even on the show? They aren't even DC Comic characters are they?
Remember, the Batman
sitcom was long, long before all DC film and TV rights were consolidated under Warner Bros. or DC Entertainment. The show was produced by 20th Century Fox Television and Greenway Productions, under license from what was then called National Comics Publications. Fox and Greenway also produced a Green Hornet
show, so they had the rights to use both of them on TV. It's the same reason IDW Comics is able to publish the just-started Star Trek/Doctor Who
crossover miniseries; the two franchises are from different owners, but IDW has the license to publish comics for both of them.
The crossovers between Batman
and The Green Hornet
were complicated and mindbending from a continuity standpoint. First off, the window cameo in which Batman and Robin recognized the Hornet and Kato as crimefighters was ignored by the later full crossover episode in which the Dynamic Duo believed them to be criminals, which was their cover in their own show. For another thing, TGH was a far more serious and naturalistic show than Batman
; the Hornet had futuristic gadgets, but operated in a world that was basically realistic by '60s action-show standards. Moreover, Batman
actually existed as a television show
within the world of TGH, and we saw people watching it on more than one occasion in the show. So the Hornet was real in Batman's universe, but Batman was fictional in the Hornet's universe.