Maybe it's an illusion, or maybe it isn't. That depends on the individual in question. If somebody's previous work experience is laying tar down on roofs, they may consider the change to an office job to be well worth the added emotional toll.
Due to the low physicality of the work, there are likely people who consider it easy work, despite the psychological impact that seems obvious to you or me.
I had a really short contract at a major tech company. It was a completely different situation, I felt that I was respected and treated well. But it was a very low paid/low skilled job. I didn't see much of any room for growth. The biggest benefit to me was that it got me an interview for an internship with that company when I went to school for CS.
I don't expect these contractors to get much long term benefit from the position. And it sounds like most quit or get fired.
