Batman is everywhere, and it's great most of the time. But depending on who you are, you're only exposed to certain parts of the Dark Knight's Mythology.
I grew up on Batman: TAS, but the subsequent shows and movies. I also played some of his video games. However, I never read his comics until I was 18 (that's another story). Because of that, I had a very narrow vision of what and who Batman was.
By the time I had gotten into the comics, Batman himself was "killed", he had a son named Damien, and a bunch of other seemingly huge things in his mythology had changed. It was mind blowing! Fun, but mind blowing. The more I read, the more the gaps in my knowledge began to fill in, and even then, I still don't know everything about Batman.
So what am I trying to say here? Well, if you're a diehard Batman fan, and you meet another Batman fan who's only seen certain parts of Batman's long history? Don't be condescending or mean, for all you know, they know something you don't.
After all, we don't know everything, cause there's always more stories to tell.