Overeducated and underemployed

1 in 5 of the general population have a bachelor's degree, so 1 in 7 seems expected, if not on the low side.

It can be an immigrant's first job in the US. I remember years ago a cabbie from west Africa who had a Ph.D. in urban planning or some such field. He had left his country because he was on the outs with the regime there.

As for bartenders, I'm surprised it's that few. Washington may be an outlier.

I think in Western Europe the ratio might even be higher. I recall a conversation with a German several years ago and was told it was not uncommon for people doing blue collar jobs to have achieved some higher education.

In any event, more education the better, even if not individually returning the time/money investment.

I'm not sure what's so surprising about this. Cab drivers aren't exactly the bottom rung of the economic ladder. Cab companies don't rent out expensive cabs to just anyone, and driving involves capital costs (either buying your own taxi, or paying the rental, which can run $150+ per day).

Right after the financial crisis, I had a cab driver who managed mortgage representatives at Countrywide before it went under. At the time there were zero jobs for people in the mortgage industry, and he was doing it to bring in some cash while working on starting a business.

Employers don't treat foreign degrees equally with American degrees, so it's very common for engineers or even doctors with foreign credentials to work service jobs like driving cabs while they "launder" their foreign degree with U.S. schooling. My uncle was a doctor in Bangladesh and then emigrated to Australia. He worked as a bell hop, among other things, while he went through Australian medical school. He owns a private practice now in some resort town.

Being a taxi driver has some advantages (especially if you are an O/O), with the big one being you get to set your own schedule. On top of that, it can generate quite a decent amount of money. I had a friend in college who drove a cab in Chicago on the weekends and he would make at least a grand during his 12 hour shift. I didn't pry too much, so I don't know if that was usual or that semester was out of the ordinary. But I would imagine that it pays better than many of the other "low skill" jobs and can offer much more variety.