McDonald's Mr. Floersch the managerial turnover was at 20% globally while that of the crew members averaged between 80 percent and 90 percent. [0]

That high turnover means that low paid employees are much faster to leave. Some don't even show up to their first day of work. It's also selection bias sure. But if you talk to anyone who manages low paid employees, the primary skill set they have is interpersonal relationships with their staff, or at least the good ones. The fixed costs are very high to hire someone, regardless of salary. You have to pay a recruiter or even spend time looking through resumes, running expensive background checks, interviewing etc.

Now consider the Goldman Sachs investment banking analyst. They get paid extremely well and get treated like crap. Do they have a "direct relationship with their employer"? Hardly.

If you're making $10 an hour its a lot easier to find another employer paying you a similar amount than it is if you're making $200k a year.

[0] https://ukdiss.com/examples/high-employee-turnover-at-mcdona...

Hell, I used to be a dishwasher then line cook at a Friendly's (east coast family restaurant, primary PA/NJ/NY/CT/MA) for two years and by the time I left for college I was the most senior person there who didn't have a key to open the building. And two of the three cooks who had keys were still in school, one HS and one college.

Managing a restaurant is super demanding work but it's not that far off from median salary. It's not as much of a dead end as people think it is, especially if you start at the bottom and work up.