Marx would say that capitalism is a machine made out of human beings; human beings are the little cogs that make the machine go round. Work is such an important topic as it relates to identities therefore because it is the place and the acts that we do at work that either reinforce our class or not. The constant worry by some to do well at their jobs because they are scared of not having money to buy food, to pay for their shelter, and live a decent life are what strengthen performance at work (or not strengthen performance at work depending on the level of need). This is why Marxs theories on capitalism and work were so right on. If a person is so worried about how they will eat their next meal, they are inextricably linked to their job performance and thus their cultural performance too.
In America, it is obvious that privileges that come with race help transgress racial (and gender) norms.
For immigrants of the 20th century (and for immigrants today as well), attaining a certain level of status — or whiteness — is the goal. Again, this doesnt mean whiteness in terms of skin color (that would be impossible), but whiteness in terms of an identity that is one of status and pride. For immigrants in the novel, transgressing identity is vital, however, it is not something that is easily done.
We know this all too well as we contemplate the problems and discussions of immigration today (especially pertaining to Mexican immigrants). There is still a certain stigma for these people who want to come to America to and achieve a certain level of whiteness. Today many of the Mexican immigrants in our country hold low-paying jobs, oftentimes as laborers, and this division in work is reinforcing identities..