I'm not talking about executives. I'm talking about rank-and-file office workers who have nobody reporting to them. Now, while there are probably some individual office workers treated worse than individual warehouse employees, the contrast is stark. Like, I work at the office of a factory. I don't have anybody under me, but the difference between how I'm treated and how they're treated is so stark. Hell, they're even union guys and I'm not.
Is there some obscure theory thing explaining this?
It's probably the association of manual labor = low skill, easy to replace, and white collar = skilled labor, difficult to replace. This is generally bullshit, the difficulty in replacing someone and their value to the company is more often tied to how long they've been working in the industry and with the company, in my experience.