Since the athletes and actors have to run the risks of getting injured and work hard to achieve success in their profession, keeping to the standards in everything like shape, weight and fashion, high salary enable them to survive for the rest of their lives for they may have inadequate capacity to do other jobs.
https://blog.papersmart.net/essay-are-actors-and-professional-athletes-paid-too-much/
http://www.studymode.com/essays/Are-Professional-Athletes-And-Actors-Overpaid-51481526.html
High salaries for athletes or actors seems to be unfair towards the professions which are supposed to be even more difficult and important like teachers and doctors.
http://www.teenink.com/opinion/all/article/24311/Professional-Athletes-are-Overpaid-for-their-Jobs/