[riffraff]

While I do second your impression that many books I liked where referrals, I'd say that the image of a customer sampling a book in a public library or bookstore seems to be quite an iconic classic, and thus it makes sense to port it to a new media.

On the other hand, while it is hard to judge a book by it's cover, it's not so crazy to judge it from a few paragraphs: if it's a funny book, you can usually tell right away if it's your genre of irony, and if it's fantasy you can see easily if it's all smeerps and naked heroins dressed in leather and so on.

Some things do grow on you during reading, but if you can't stand a pompous verbose style (or a crude bare one) you can avoid starting reading something you won't ever even finish.

But, obviously, all of this is IMO.