"War heros" are different from other celebrities. A singer has chosen a life that will, presumably, make them famous. They should be prepared for the criticisms that people offer, although even that, I think, should be limited primarily to their skills.
A soldier becomes a hero, usually, by being an average person placed in a horrible circumstance, and rising above that. There's no part of that equation where he or she should say, "Wait, if I rescue all my squadmates from certain death, I will have to face possibly being publicly humiliated on television. Do I really want to do this?"
And even if they were talking about the latest American (or Australian) Idol, there is no reason that they should be making snide personal remarks. It's not part of civilized life, but the media are quickly trying to remove civility from public discourse. And then wondering "Why are you common folk getting so much ruder these days? Just because WE do it doesn't mean that you should!"
My late aunt had a saying:
Great minds discuss ideas.
Average minds discuss events.
Little minds discuss people.
Clearly, the people on the show were displaying their own "little" minds, rather than their subject's.
