I'd like to correct that with "they believe they don't have an alternative." Almost all of them can get a better job, and that's why they are leaving bad employers and bad industries. Information is traveling faster than ever right now, and people are waking up. Gone are the generations of older people recommending a young person to take a shit job. Instead they are getting advice from the middle generations who have already been burned to stay far away from these jobs. Even people at the bottom have mobility and will go where better opportunities are found.
> Of course stuff like farm work and grocery stores are low paying, so it's not like they're just going to disappear.
Farm work has been massively automated with tractors and harvesters, those jobs have mostly disappeared. Today but a tiny percentage of the work force are employed in farming, when before it was the majority of the population. Grocery stores have changed as well. When before there were clerks handing goods over the counter, now people grab their products from shelves.
That's what we should call a "Low value" business, which is actually what many businesses and entire industries are in the real world. Restaurants say they can't find workers, when the truth is pay and work conditions cannot attract workers. They say they can't afford to pay higher salaries, the response is "then raise prices". They say "then we'll lose our customers". Good! The business is not valuable enough and that means customers have to do without.
There is absolutely no need to continue with low value economic activity.