These actors on either side of the border have a huge fan following, any comment or support from them which goes against the demand for water (from TamilNadu) and the demand Not to give water (from Karnataka) will not be tolerated.
As far as controversial content goes, the makers of the movie often have to balance the boundaries of creativity and the limits of treading on controversial topics. But often the trouble comes for few vested interests who fuel the anger among people. But it all depends on how the subject is handled. The movie Bombay by Mr.Mani Rathnam is one of the fantastic examples of how to handle a controversial topic. In this movie, there is a Hindu-Muslim love marriage and the violence due to the destruction of Babri Masjid.
Cross border events are one more area which are depicted with exaggeration in the movies. Patriotism is one area which is evergreen to attract the attention of cinema fans.
Sometimes some of these ingredients become very critical and controversial and either the movie will have to be removed from the picture halls or it may be making huge money in box office.
So basic intentions are publicity and making money but what way the public will take the controversial contents is known only after the release of the movie.
Knowledge is power.
So, for me this could be the stunt in order to create more curiosity to the audiences so as to increase the viewership.