I originally heard an excerpt of a dramatization of a Zola book on Radio 4, and that piqued my interest. I got Pot-Bouille from the library and found the book interesting and enjoyable (with a grim bit at the end) while delivering a strong moral message.
I think the purpose of the book is to highlight the hypocrisy of the bourgeoisie in their sexual conduct. Published in 1882, the book made me wonder if the problems that Zola raised have been solved by paternity testing, contraception and child support. My view is that the main physical problems have been solved, but there's still potential for psychological problems. What do you think?