unions

What point are you trying to make? Part of the discussion on the term 'unskilled' labor is that it helps justify lower pay, when everyone should be paid at least a living wage no matter the 'skill' level or replaceability of a worker. There is useful meaning to the terms 'skilled' and 'unskilled' in labor but people view it as disparaging to jobs like cashiers or waitstaff because there are skills that are required to do those jobs well, though obviously different than being trained as a welder or another trade.

By referring to these jobs as 'unskilled', people will have less of a problem with workers in these positions being seen as replaceable, because 'anyone can do it', even though if you've ever been a waiter or in a similar 'unskilled' job you'd know it's difficult and not everyone is capable of doing it well.