in principle i agree with these schemes. if someone has been out of work surely they get lose some of the discipline involved - ie getting up in the morning, doing something they don't like all day, and dealing with people etc.
just two provisos - it doesn't reduce paid employment (ie substitute someone paid for workfare person); and if someone can find a more suitable placement themselves they should be able to do that. so think the lady should have been allowed to work at the museum if that was her career choice.
i've done unpaid jobs and very low paid jobs. some of my children are doing unpaid voluntary work. in my volunteering job one of the kids was amazed that my son would work in an old people's home for free because it was good for his CV. some people seem to think they are above all this.