Well even though it's not good and sucks to experience, it does make sense to me. For most people, our jobs are the difference between staying afloat and dying on the streets. There is so much serious significance behind employment that it's almost never "just a job" whether you're a physician, a programmer or a waitress. So I think when there is a lot of stress at work itself, it can easily provoke a crap-ton of more primal stress about survival, taking care of family and so on, even if it's all on a subconscious level.

I'm currently working as a cashier in a gas station, and more often than not I have nightmares about being at work and things going wrong. It's craziness.