I always hear people say that part of the appeal of Batman is his villains which I agree with because I think he has the best rogues gallery in all of comics. But some people seem to think that they have more appeal than they actually do, some people even make it seem like his villains are more popular than he is. That idea is laughable, outside of The Joker which Bat villain is even remotely close to Batman in popularity? It's usually people who hate Batman that I hear say things like this "Oh people only read Batman because of his villains!" sure that may be the case with a small section of the fans but not for the vast majority. It's like yeah maybe a small group of people only read Superman comics for Lois Lane but the majority buy Superman comics for Superman. Lets look at Batman's most famous villains and their popularity among comic and non comic fans. I'm leaving out Catwoman because she is more of a anti hero.
The Joker: Extremely popular, the only one of Batman's villains with big mainstream appeal imho.
The Penguin: Considered a joke among most non comic fans and even a lot of comic book fans.
The Riddler: Same as Penguin.
Two-Face: Popular among comic book fans, most non comic fans seem pretty indifferent towards him tbh.
Ra's al Ghul: Popular among comic book fans, most non fans either don't care about him or don't even know who he is.
Bane: Popular among comic fans, decently popular among non fans ever since The Dark Knight Rises.
Mr. Freeze: Decently popular among comic fans, non fans think of Arnold and his corny puns.
I'm not trying to bash his villains or anything I just think that sometimes people overrate the popularity they bring to the Bat universe.