Some want jobs because it's all they've known and they don't know what to do with themselves without one. I imagine some of these people would find things to do if they had more time and energy to spend on things other than recovering from/for their jobs.

Some have that answer because they think it is entirely unrealistic to create or have the idealistic society you describe. I am part of this group. There are many things I have on my backlog that I'd like to accomplish, but too much of the required time and energy is taken up by my job. Yet, I still hold onto it desperately, because the alternative is much worse, and I have no way of fixing that.