I think that Crooks is disadvantaged because Steinbeck shows him struggling with both the marginalization of race and class. In this light, Crooks deals with more than other characters in the novella. Like the other ranch hands, socio- economic reality plays a central role in defining his existence. Like the other ranch hands, Crooks is hired to do a job and must deal with the fact that he lacks a sense of economic autonomy. However, unlike the other ranch hands, being a person of color in this setting causes doors to be closed, opportunities to be denied. Crooks' discussion with Lennie reveals how he is afraid or apprehensive to dream because he cannot do so. Steinbeck is making the argument that a person of color in this economic setting cannot afford to have the same dreams as others. This is shown by his initial apprehension and resistance to the dream that Lennie and Candy share with him. Yet, after hearing their zeal, there is a part of him that wishes to partake in such a vision, almost as if hope is creeping back into his psyche. The cruelty of this is undercut when Curley's wife reminds him of his place in the world, and with a stunning bluntness, he reminds Candy that he wishes to have no part in such a dream, going back to the isolation of his own room and world. It is this condition caused by a convergence of race and class that prohibits Crooks from living a life where hope and redemption is possible. Crooks suffers from carrying the weight of the past to a level where hope for the future is absent.
In Steinbeck's Of Mice and Men, Crooks is perhaps one of the most disadvantaged, desperately seeking to be accepted in a harsh world. Like all the other lonely workers on the ranch (proven by Slim in,
"none of the guys ever travel together... You know how the hands are, they just come in and get their bunk and work a month, and then they quit and go out alone. Never seem to give a damn about nobody."
Crooks also says to Lenny when he hungers for a little companionship:
" He whined, "A guy goes nuts if he ain't got nobody." ... "I tell ya a guy gets too lonely an' he gets sick." "
And in the last part of that quote he is referring to himself, a victim of not only racial discrimination but also the cruelty of loneliness that everyone on the ranch faces.
Crooks is not only just looking around for work during the Depression, he is in fact COMPLETELY isolated from any human contact due to his skin colour in a racially biased world.
The true nature of this discriminant world is possibly best proven on Page 80 (in my book anyway, it's section 4), where Curley's wife harshly scorns Crooks upon the basis of his colour:
"She turned on him in scorn. "Listen, Nigger," she said. "You know what I can do to you if you open your trap?" | Crooks seemed to grow smaller, and he pressed himself against the wall. "Yes, ma'am." | "Well, you keep your place then, Nigger. I could get you strung up on a tree so easy it ain't even funny"
By the way, the | indicates a paragraph in the novel, just so you know who's speaking ( Curley's wife -> Crooks -> Curley's wife)
It is clear that Curley's wife, in her own loneliness strikes out harshly against Crooks, and Crooks accepts what she says:
" "It wasn't nothing," Crooks said dully. "You guys comin' in an' settin' made me forget. What she says is true." "
Thus, Crooks is arguably the most disadvantaged character in the novella.
He is disadvantaged by his race. He is black and they are all white so he's treated differently. He has a crooked back. His class is low.