I think part of the problem is that the comic books over here are usually running multiple story lines at once. It can get quite confusing at times.
A great example would be Spider-man. Just look at the sheer number of titles for that one character. Then you have to add in all the crossovers and
god forbid we get into the whole Marvel "what if" universe. LOL
I agree that I would be happier to see more tv shows/ movies follow their comic book storylines a little closer but I think the fall back is they have
to make it something the average consumer can jump into.