Exactly. They're dressing like that in an attempt to get the point across that it's OK to be overweight. I'm sorry, but it's not. It's unhealthy and it puts an increased strain on your whole body which can lead to cardiovascular disease, diabetes, osteoarthritis etc.Being big is fine, but trying to convince genuinely fat girls that being 20 stone+ is fine? definitely not!
Not to mention the fact that it's not aesthetically pleasing either.