It’s just what’s done in films, as the film industry is completely and utterly submersed in fatphobia and fat discrimination. How could you watch any films and seriously ask this question? Because most of them aren’t specifically about thin people, yet the vast majority star thin people, even the ones not set in 19th century France. Weird, right?
(and you might consider leaving out the parenthetical not-trying-to-attack-you. Because folks who write in with serious questions don’t have to qualify them with “but I’m not attacking you, seriously!”)
Edited to add:
pastelpasties said: I think the problem with this is that Les Mis is very much about the poorer, lower class. Back then, no money=no food=emaciated.