That's not really the point.
The book is not a socioeconomic study of the characteristics of poor or uneducated people. Rand thinks that shit is for liberal losers. It's a (horribly bad) philosophical/metaphysical treatise.
Think about the whole point of the book. It's to reject collectivism, which is the subjugation of the individual to the group-- whether that group is based on class, race, or whatever.
Rand's attempted point is that racism is just one form of collectivism, and collectivism in any form is bad. And yet she lumps people into groups willy-nilly. More so than even the average weak, liberal loser. So she's being a total hypocrite there.
Moreover, her attempted point in that specific chapter is to say that racism follows from collectivism. In other words if you think in terms of groups at all, you will inevitably become racist.
Except that there are plenty of people who are not "objectivist" who aren't at all racist and think it is stupid. I'm guessing that all of us fall in that category. And it's because the problem with grouping people by race isn't the fact that you grouped them, but rather that you grouped them STUPIDLY. There's no scientific or logical reason to believe that blacks are stupid or lazy, or whatever.
Conversely, most racists are not like "Gee, I need to subjugate myself to the needs of the group. Therefore, as a white guy I will regretfully accept property and riches as a self-sacrifice." See what I'm saying?
She says she is above collectivism, yet she stereotypes like a mofo. Other people are not above collectivism, yet they don't stereotype less than she does. So how does collectivism lead to racism/classism, etc.?