I read the classics as a kid. But I read great gobs of other stuff, too--science fiction, Westerns, Nancy Drew, you name it.
Grown-ups tried to tell me the classic books were somehow better, nobler, because they had "stood the test of time." I didn't buy that. I liked some of the classics, sure, but I liked pulp fiction too, and I saw no difference. If a book grabbed me, why should I care what my descendants would think of it? The only test that mattered to me was Right Now. We judge a cake by how it tastes in the mouth, not how long it lasts on the shelf. Why should literature be different?
Well, I've grown up, and now I've switched sides.
Popularity v. durability
Today, I do see different kinds of "good" in literature. There is blockbuster quality and there is classic quality. There is wide appeal and there is long appeal. I don't know that one is "better," but the two are different, like space and time.
That's not to say they're mutually exclusive. A popular book can also be durable. But blockbusters don't necessarily become classics; and classics don't have to go through a blockbuster phase.
And yet...