And it's hard to imagine a world in which no one knows the name "Adam West," but when he was cast as Batman, his most recognizable role was in a Nestle Quik commercial. People were paying to see Batman, dammit, not an even passably good actor.
Things started to change when Michael Keaton was cast, beating out Hollywood hunks like Kevin Costner, Mel Gibson, and Bill Murray. At the time, fans were scandalized by the idea of Mr. Mom in the cowl, but all the marketing still revolved around the bat and not the man. That's why when Keaton decided to leave the franchise, the studio didn't even hesitate to recast the part with Val Kilmer. And when he left, they threw the costume and a sack of money at George Clooney (or "the guy from ER," as he was called back then). The thinking went that as long as there's a vaguely human-shaped bulk inside the Batman suit, who the hell cares who's playing Bruce Wayne?
We all know how that turned out.
Sorry, we're legally required to show you this.
That's what happens when you give more importance to the mask than the character: Memes are born. Keaton, Kilmer, and Clooney are completely different actors -- imagine how nuts it would be if Iron Man 3 started with Channing Tatum playing Tony Stark, and then in Age Of Ultron he's suddenly Dwight from The Office. On the other hand, think about the single most memorable superhero movie villain ever: