Introductions - Who Needs Them?

After reading a dozen introductions in one sitting (see rare book find), I don't see the point of introductions. Or rather why it has to be in the first few pages. Most of the people who write introductions are either trying to sell the book or explain it (sometimes both). If it's the former, it's like an essay-length blurb. And honestly, by the time you're reading the introduction, you've already bought the book. If you're trying to explain the book, wouldn't it be better if it was placed at the end, once people are done reading the novel?

Of course one could hypothesize that we're borrowing the book from a library, hence the importance of an introduction. We're making a what-if scenario that people will borrow a book based on a well-written introduction. But can you honestly tell me that's the case? Have we borrowed or read a book because of the introduction? I've heard of people reading a book because their teacher ordered them to do so, or because their friends told them it was a good read, or because they read a raving review. I've never heard of "it had such a great introduction that I'll read it!"

Okay, so maybe the introduction is part of the marketing strategy. It's another way to sneak another popular person into the book when you ask them to write an introduction. But if that's the case, people are buying it based on who's writing the introduction, not because of the introduction itself. The person in question could write a one-line blurb and the book company can say it's an introduction. I don't think people will really notice (yes, I'm exagerrating). The way I see it, wouldn't it be better if introductions were way more accessible, say at the back cover of the book instead of the first few inside pages? That way, people will immediately spot it, and reading it will actually have an effect on influencing whether the reader will buy it or not. Maybe I'm just a product of my culture wherein brand-new books are shrink-wrapped.

But honestly, when we browse books, I don't think we really settle on the introduction. We might look at the table of contents, the prologue, and some even the epilogue. I don't think I've lingered around the introduction section, especially considering the introduction is the one part of a book that could change with reprints and different editions. But apparently it's important enough that book publishers look for someone to write the introduction, and that someone isn't just anybody. I guess someone has to write 'em.