They factually aren't starter jobs because the people overwhelmingly doing them are people that need to live on those wages.

Low end jobs cannot meaningfully structurally serve as stepping stones within an organization because such professions/companies need massive amounts of low wage labor, very few better paid workers, and most of the actually well paid positions are available via an expensive education not earned by hard work within the org. That is to say Burger Bob's thousands of franchises need tens of thousands of flunkies, hundred of slightly higher paid flunkies, and dozens of high paid people who are mostly recruited out of college or industry.

This is to say statistically approaching zero of Bob's employees can escape poverty by working hard for Bob. The alternative is imagining that a peanut butter sandwich can feed a stadium full of people because in theory any one of them could eat it.