Modelling...fake?

I've just finished watching America's next top model! The glamorous life of a model! Or it would seem not in these model's cases. Constantly travelling up and down the country. Constantly getting criticised for the way they look. Constantly having to act cheerful! Maybe this glamorous life isn't so glamorous? These girls are constantly telling each other that they're fake and that the act they're trying to pull just isn't working. But is it possible to be fake? If a person acts all smiley for the cameras, but as soon as they're off they turn, does this mean that they're fake? Surely this is just who they are? Someone who tries to act up to the cameras and tries to look picture perfect to the public. And if that's being fake, then are we all fake? I can honestly say that I've never met anyone who doesn't change in certain situations. If we turned up to a job interview and talked to them like we talk to our friends, then we would not get the job. But, I don't think this makes us fake. So if a model went to a public outing and acted all smiley and happy, does this mean they're fake? Or does it just mean they're trying to please people? You tell me.