i'm not one to fall into the orwellian language of contemporary social activism, but they have a term for this - they call it "silencing". no, not them - you. i know. it's ironic. and logically problematic. but, they nonetheless have somewhat of a point. telling people to shut up is telling people to shut up, regardless of the context.
i think it's an error to assume this was merely a comedic routine. i mean, we can see she was trying to draw attention to herself, sure. but, you've got some emo running in the background, so i'm going to assume you know a little about punk rock - you create a ridiculous platform for the purpose of getting a serious message across, not the other way around. i think it's more that she was making a point by being shocking, rather than she was being shocking for the sake of being shocking.
and, the purpose of anybody doing this is to start a discussion.
so, let's have this discussion, then. is over-eating to the point of being unhealthy something protected by individual rights that we should accept as a personal choice, or is it anti-social behaviour that affects everybody negatively and that society has a collective right to try and coerce people away from?
but, keep in mind that while the obese may be a minority, they're a third of the population. that's larger than virtually any other minority you could articulate.