Like they just act for the $$ and not for the love of acting (as all celebs say when they are interviewed thatn since tey were little they wanted to become actors/actresses, the same cliche response).
For example I heard many tv/movie stars when hired to play a specific role in a movie, some turn down the role cause it may go against their principles or the way they think of certain things or because they can't be away from their families to long (when the movie requires to work in anotehr city or country for more than 3 weeks or so) among many other reasons celebs may state as to why they can turn down a role..
Do you believe that a good integral actor means they have to play different roles in their life and not make the same old characters always and at the end they are typecast for playing the same character always in al the movies they do? For me Jennifer Aniston is one of them but of coruse tehre are many others.
For example a good whole integral actor could be Johnny Deep, Al Pacino, Robert Deniro, Meryl Streep, Charlize Theron, Nicole Kidman they had played in the past different roles. For me is because they enjoy what they do, they do love acting and they like to becoem different characters, of course the pay comes for palying such different roles, but maybe they enjoy more acting and dotn care so much for the salary they are going to receive.
Also happens I heard with actors who go uncredited on movies, I heard (dont know if this si true) some celebs do it as a favor for the friendship they have with the movie director, or
I heard of some known actors who had gone uncredited in their movies because they also are not really recognizable in their movie roles. There was one actor who starrred with big names on a movie asome years ago and he went uncredited