All labour is skilled labor. Unskilled labour was created by capitalists as a flimsy justification for paying people unlivable wages. ANY labour deserves a livable wage. Needing a second job is an injustice.
Now that being said, packing boxes for Amazon is 100% unskilled labour. A machine spits out the box template sheet with creases where the cardboard sheet should be folded to turn it into a box within seconds. Another machine prints the receipt that goes inside, and Another machine spits out an appropriate amount of packing to make sure the product stays in place inside the box. Another machine spits out a calculated amount of tape. Another machine spits out the info sticker that needs to be stuck on the outside.
Does this need a lot of skill or training? I don't think so, no.
If McDonalds didn't care about effectiveness they wouldn't be a household name, let alone an international corporation. People talk down about fast food, but it isn't their business strategies that are bad.
I think the problem is that people don't get paid enough to care anymore. Not even the managers. There's too much wealth hoarding at the top in the US.