Apple fires employee

Based on my understanding of the article i feel the U.K based apple store was well within their rights to fire the employee as long as they had made clear the companies policies on social media. In the article it stated that " Apple, made it absolutely clear throughout the induction process that commentary on apple products, or critical remarks about the brand were, strictly prohibited". So by choosing to do so the employee knew the risks of his comments on the Apple products and should have not even appealed the decision in my opinion. As the employee because i was informed on the companies policies i wouldn't post positive or negative comments regardless of the social media avenue i'm using is private or not. Now as the employer i would expect you to obey the company laws and the fact that the policies were explained before you were hired and so i would do exactly what the company did in this case and fire the employee.