Simply put, the Krause fellow was being a dick. He's not a regular follower of the show and doesn't personally know this woman but feels compelled to lecture her on her weight. What a troll.
Sounds like what Michelle Obama did to Gabby Douglas on the Tonight Show.
The so-called "epidemic" of obesity (it's not an epidemic since it's not a communicable disease) is being used by nanny-state types in government to try to bully people into living a lifestyle of which the nanny-staters approve: look at Michael Bloomberg in New York City, for example. And yet when it's the government that's the bully, somehow the evilness of bullying suddenly gets overlooked.