There's a difference between body positivity and being overweight

I'm all for promoting body positivity and not being paper thin to be healthy. It's normal to have fat. But some people who are genuinely overweight will justify it with "loving myself" and so on. I know some people are overweight due to medical problems, that's different. Especially the overweight people who get mad at the world not accomodating them (seat sizes, clothes, etc) and when people tell them to lose weight they call them haters