And there are lots of people walking around with bad haircuts who think they look great.
Of course the same person could work either place, and cut hair accordingly. Int, this day and age, a barbershop typically means a clipper-based haidcut for men. No matter how 'good' you think your clipper haircut looks (and I've had many, given them to myself when I've been short on cash) it still looks like a cheap clipper cut, and all clipper cuts 'chew' up your hair, meaning they grow out like crap. So you could spend $15 on a cut you need cleaned up every few weeks, or $50 2-3x a year at a decent salon that will give you a free "cleanup" or two.
I'm pretty sure the feelings around this are as much based in culture as economics.