The harder you are to replace the higher is the chance to get good job, and job at all.
Of course in some small towns(like mine) you can't find job like, let's say astrophysicist. Just now way. But if you are good in your job, you can go(if you want) to some bigger city and get a job.
Story time:
I know a man who was mechanical engineer (IDK if this is how you call it in English), he was really good at his job but decided to come home (he was working in city that was far from our town) because he wanted to find job here. People from the company literally come to beg him and said that whenever he decide to get back they will immediately put him at his old position(he was in charge of the whole team).
He decided to stay here. People were coming to ask him to do different work for them, he was working mainly with the military in the town, no steady job and he was overqualified but was making good money. Now he is retired, there is no more military and barracks in our town. Now this man is old and not in condition to work and get some retired pay (around $200 month just because he is sick and old) with which he can only pay for his medications/drugs that keep him alive.
Moral of the story? You are right about rural areas. Especially in not very well developed countries.
On the topic:
I know a lot of people with "smart" degrees. Like programmers, mathematicians, physicists, jobs which you can also work from home sometimes... Oh, man... That's only what the degree say, they never have shown interest in these fields, they know nothing about these things... How they got the degree? Magic!
I also know a bunch of people studying computer science, they are third year students, show absolutely no interest in their education and have absolutely no knowledge in this field. The only thing they care is "where will we get drunk tonight". Why the fuck are they wasting their parents money?! And how the hell they managed to pass the exams? Magic? And more importantly. They think that after they take the degree, they will work that. Can you believe this? I simply can not.
TL;DR: If you are good at your job (which is some of these "smart" jobs) and your kids are hungry. You can almost always find a job and feed your kids.