> Most people aren't willing to crawl underneath houses to hook up potentially-dangerous electric/gas lines. etc.

In a past life, I tried the general laborer gamit and it's impossible to get a job there too. Simply cause nobody hires you unless it's by word of mouth. So it's even worse than being shut out for not having a degree. So overall, it's no so much that people don't believe that they need a degree, it's the path of least resistance since you can at least get your foot in the door through a company once you pass the minimum qualifications. General labor stuff, good luck getting a job in a specialized field. I tried breaking into HVAC and I couldn't even get an unpaid apprenticeship cause people just won't do it.