Unless you have tried it don't entirely knock it. Back in the 90s I was an assembly line welder in a Japanese auto plant (paying for school among other things), also mounted doors and fenders. What was interesting is the plant had many educated career people working there post other successful careers. Business guys, bankers, lawyers, teachers, engineers, etc.
Why? It paid good enough for their situation. Comparably from what they left very little work stress. Never bring your work home. House was paid off and kids were done school so they did not need the money they were making before (and in some cases it was comparable) but not ready to totally retire. No difficult clients to deal with. Pretty much no out of pocket defined benefit pension plan (at the time). Not hard work but you are mobile, not riding a desk, that has health benefits (plus in my case we lined up and did all the exercises in the morning). Show up, do your work, go home...
Yes the work is repetitive but it has some advantages. In a true TQM enviroment the line workers do have some input BTW. As a life long choice it may be a little too much though. When I reach the above situation (house, kids), I would consider the same approach.
