I don't know why film stars think they have the right to do this. They just provide a service which consumers can take or leave. Exactly the same as the person in any shop which I buy anything from. I don't want or need their political opinions, just customer service.
Film stars and other so-called 'celebrities': take note. Just before Brexit, 'luvvie' film stars like Hugh Grant and others, went on British TV denigrating those who were pro-Brexit. Instead of helping their cause, the Great British public realised they were being spoken down to by privileged minorities (in the case of Hugh Grant, with a criminal record (It's twenty years since Hugh Grant was arrested with a sex worker), and their campaigning probably went against them, because they lost.