The reason why the game box contains 4 (!) books, a sheadload of cards, dice and templates is that FFG wants to make it seem that you get a lot of stuff in it, and that the high price tag is really kinda worth it. Whereas if it was just one book, how would they justify a 100 dollars price tag? No way.
The fact is that all the stuff that comes with the box is cheap as mud to manufacture, so they make a huge profit compared to the old book RPGs. Don't be fooled by the shiny things. Just say no.
As to the four books, why make 4 of them when you could have made just one? Exactly, it's because they want to fool you again: see you don't get 1 book, you get FOUR!!!
It's like those TV shop networks, lot of noise and extras but the actual product is crap.