As has already been posted the degree can get you the interview.
Chilehead, a person with a 4 year degree or even 5-6 year (masters) probably isn't looking to become an irrigation installer or laborer of any kind. And I agree when it comes to more of the labor type jobs you need someone who can do that job and has experience doing it. But they didn't know it all when they started......
Most of us, I didn't say all, are not going to college for 7 years to get a labor type job. Maybe we end up in a labor type industry but as managers or foreman. We are hoping this formal education will land us in jobs where we hire companies like the ones most of us run to do work for us or buy a $10,000 zero turn to mow our own lawn because we can afford it to blow $10 grand on a mower we don't need. The companies that hire in the jobs we get the degrees for use it in their hiring to eliminate a lot of wannabe's and unqualified people. Also many of the college kids I know, along with myself, spent a year or 2 doing internships to get that hands on experience. Most are unpaid but I've seen many business degree type jobs paying their interns low wages and training them for a year. Then once the person graduates they get a qualified individual who knows what they are doing but also has the knowledge base from college. Also when it comes to sales, that's more about personality than anything. But even most salespeople get good sales training.
Every friend of mine with a higher education, maybe even myself included, live pretty good lives. The ones that dropped out of high school or never went to college are either stuck at their job, can't get a better job, and have to punch a clock.
College isn't for everyone and no it's not needed to own a business.