Donald Trump is very clearly a media hound who only is concerned with getting attention, positive or negative. The celebrities who appear on his show are trying to cling to their 15 seconds of fame and will do anything to hang on to it. Trump takes advantage of them, and will do whatever he can to promote himself.
Donald Trump does indeed take advantage of his contestants, as this is his entire business model. He's just out for exploitation and wants to take advantage of as many people as possible to make as much money as possible. It's the name of the game for people like him in our society.
Yes, Donald Trump takes advantage of his contestants on "Celebrity Apprentice". In the show it seems as though he uses his contestants to do all his dirty work and if they do not comply he fires them. I believe this show is a disgrace and is purely used to promote Donald Trump.
Of course Donald Trump is taking advantage of his contestants. They're performing work and aren't getting paid for it in a standard way. All of these contests we see on TV are taking advantage of someone. Free work is becoming quite common in America to get experience or for something to add to a resume. That doesn't make it right however.