Society cannot function without garbage people. It must be done or society will collapse quickly, so society better find a pay rate that gets the job done.
Not everyone wants to work in an office; some people really like working outside and being indoors is like prison.
But you're right, the job isn't as bad as it used to be.
I remember being in a meeting once when a manager looked out at the guys on a scaffold cleaning the windows and remarked "at least we don't have to be out there like them." My first thought was that they were probably thinking "at least we don't have to be inside like them."