My thought when I read about the world's first waterproof paperback was, What kind of gutless reader needs a waterproof book? Back in the day when I had time to read in the bathtub and at the beach, I read hardcover books over water. I read hardcover library books in the tub and while sitting on the shore pretending to watch my kids while they were playing in the lake.
Come on, any true reader is willing to risk the cost of replacing a book--particularly a paperback book--for the chance to read any place and any time. What's more, the danger adds to the thrill of the reading experience.
When you see me reading a waterproof book, you'll know I've lost my nerve.