It really looks like you have a very shallow understanding of this game. You do realize that without raiding, crafting and gathering would be totally pointless, right?
Again, you do you remember what happened in 3.1, right? The raiding scene almost died, and the crafting and gathering scene died with it. Did you ever wonder why they decided to introduce the savage and, later, the ultimate difficulty?
Come on, it's not so hard.
But the point remains. Savage and ultimate content are the sole reason why a good chunk of the player base keep playing after reaching lvl 70.