You previously explained that that is how it worked for government jobs etc.. and then went into detail on that.
I think the jobs are different and that someone getting up early and working outdoors in all weathers, doing physically demanding work would probably be doing a less desirable job than someone putting the plates out. Without wanting to go back to the whole "thats how it works/govt jobs thing" I don't see why they should, in principle, be compared in the first place.
Well I do not fully agree with it. For Physical demands dinner ladies are classed as
“Walking, bending, stretching, lifting, moving and handling furniture and equipment form a regular part of the job”
Which is pretty much the same as a binmen. Loading a bin onto a lift thingy is seen as the same as lifting a table.