If you decide to be an actor, stick to your decision. The folks you meet in supposed positions of authority—critics, teachers, casting directors—will, in the main, be your intellectual and moral inferiors. They will lack your imagination, which is why they became bureaucrats rather than artists; and they will lack your fortitude, having elected institutional support over a life of self-reliance. They spend their lives learning lessons very different from the ones you learn, and many or most of them will envy you and this envy will express itself as contempt. It's a cheap trick of unhappy people, and if you understand it for what it is, you need not adopt or be overly saddened by their view of you. It is the view of the folks on the verandah talking about the lazy slaves.
There is nothing contemptible in the effort to learn and to practice the art of the actor—irrespective of the success of such efforts—and anyone who suggests there is, who tries to control through scorn, contempt, condescension, and supposed (though undemonstrated) superior knowledge is a shameful exploiter.— David Mamet, True and False: Heresy and Common Sense for the Actor
I haven't had to deal with this in awhile, but I will again, and it is a good reminder regardless. And it is applicable to all the arts (sub your own field in for "actor" at will).
Emphasis is my own.