That's because you don't understand investing. Investing in an 18 year old who plans to work at Home Depot will return nothing. He will be worth nothing in four years, and will be worth nothing in ten years. He will have no savings and will be breaking even. The guy going to college for engineering will have unlimited potential in four years, and just by virtue of the fact that he was accepted to the engineering program makes him a better investment starting day 1. The other stuff about $200k debt is silly. It doesn't cost that much, and five of my six kids all went to college with very minimal debt.
Unless someone gets a worthless degree or goes wild with loans, education is always the best investment. It's the same with business investments: potential is one of the most important properties to evaluate.
Go start a business and get back to me on that.
There are plenty of great businesses that go for years producing great products and services that turn the money back into the company, essentially investing in themselves. The bottom line won't show that they are making money, but they are increasing in value. Companies who don't do that will not make it long term.