I don't know of any minimum wage job where someone can use it to improve their skills.
I know of several:
A ranchhand learning how to handle animals (yes, that means shoveling shit as part of the job), and increasing his skills to successfully being a ranch owner himself.
A slot machine mechanic learning about his chosen field in electronics or computer programming in a trade school or college.
A fast food worker learning about the basics of customer service and holding a job (you know, showing up on time, being responsible, etc) while they are going to school earning a business degree.
An airport fuel lineman or even a baggage handler while they learn about being a pilot or aircraft mechanic.
An apprentice learning to wire or plumb a building (on the job training).
A man selling hot dogs from a cart while he learns how to sell things to people, perhaps eventually become a successful marketer of products, making hundreds of thousands of dollars a year or more.
You are making an argument of ignorance fallacy. These opportunities exist out there and are used this way, despite the fact that you can't see them for what they are.
Most of those jobs involve doing things that people my age learned through daily living.
Doesn't 'daily living' involve producing something at some time?
Is it that those college graduates never learned to apply themselves or that the field in which they choose to apply it is worthless?
It is both. There are worthless college courses and there are great college courses but the graduate never applies himself.
There are college graduates that are very good at what they do.
Indeed there are. There are also those that never attended any college at all that are very good at what they do, and make good money doing it.
The problem is that very few, if any, place a lot of value on what they have to offer.
I disagree. The problem is simply one of laziness. Anyone that applies himself to their own success, regardless of their education, WILL succeed. Those that do not, simply fail.