Why did old school superhero/comic book movies use made-up villains?

[Al_The_Strange]

I remember "Batman Returns" marketed the two main villains, Penguin and Catwoman, very heavily. I barely ever considered Max to be anything more than a side character. It wouldn't surprise me if they made him up just to give Christopher Walken something to do.

I seem to remember "Dick Tracey" having a whole mess of classic villains on screen, just with limited screen time.

Otherwise, most of these other movies are pretty weak to begin with (at least the ones I've seen are). Having weak villains strikes me as just another symptom of bad filmmaking.