He did clean off the salmon and mopped the juices with bread till the plate was bare. He's opening up and getting deeper into the meaning of the book. And it's the disgust that he feels about the institutions that bother him. The end of the book is a place of pure joy. It's better to say if you're sad, then you're sad.
People lie more and more.
The other problem is political correctness. You can't say what you think anymore, so it's a strange situation. The idea of religion plays an important role in the book. Houellebecq doesn't seem to have a real need for it, though he claims it's the decline of it that is partly responsible for destroying morality. But he's hopeful that a new religion is possible from all this decay.