Because as we all know, all fat people are disgusting slobs who bring their condition on themselves, and all skinny people take wonderful care of their bodies. /sarcasm
Yeah... but more over, the weird thing is we have a weird anomaly where society is either overly offended or not offended enough about things, and it gets into this whole weird health versus acceptance thing that's incredibly baffling.
On the one hand, there's this whole anti-airbrushing body acceptance thing that works up to a certain level of chubbiness where if anyone says anything, they're a complete monster... yet larger to really heavy people are still shamed, but in a weird passive aggressive "we're only worrying about your health" (but totally not) way. It's confusing. You have to be in the very
exact middle of hyper thin and obese to not be seen as some sort of degenerate or sob story.
Say a girl who is kinda chubby to the point of just over having curves. She posts a picture of herself on something, a bunch of trolls fat shame her, the media picks it up, and she's a folk hero. Now, let's say the same girl is like
really big, wearing something completely inappropriate for a very specific audience. The media picks that up, and now she's a disgusting monster that we feel sorry for because she's endangering her health, and drag her out as a "see what you're doing to yourselves" cautionary tale. They then, hypocritically, do the same for anorexia "victims" again making the middle sized person look like the perfect mix of folk hero and size shaming shaming.
In other words, they want it both ways and neither ways at the same time.