For all of you like me who can't bring yourself to walk by a bookstore or browse an on-line catalog without buying at least something, and who also know good and well that you aren't going to read everything you buy, at least right now, here's an anecdote from the life of Umberto Eco that should give you encouragement to keep it up.
From the introduction of part one of The Black Swan by Nassim Nicholas Taleb:
The writer Umberto Eco belongs to that small class of scholars who are encyclopedic, insightful, and nondull. He is the owner of a large personal library (containing thirty thousand books), and separates visitors into two categories: those who react with "Wow! Signore professore dottore Eco, what a library you have! How many of these books have you read?" and the others -- a very small minority -- who get the point that a private library is not an ego-boosting appendage but a research tool. Read books are far less valuable than unread ones. The library should contain as much of what you do not know as your financial means, mortgage rates, and the currently tight real-estate market allow you to put there. You will accumulate more knowledge and more books as you grow older, and the growing number of unread books on the shelves will look at you menacingly. Indeed, the more you know, the larger the rows of unread books. Let us call this collection of unread books an antilibrary.