The biggest sales I've made to people have been some of the dumbest people I've served. This is in retail in boutique though.
I've sold HD800's to people who knew nothing about audio in depth to half a dozen people. I've sold one to an asian man who listened exclusively to podcasts on a sansa clip. An AKG k3003 to a man who simply wanted "the best", also sold him the HM-602 to pair with it. He didn't know about sample rate, file types, dacs, headphone amps (desktop/portable). He just wanted the best and needed me to repeat it to him. I told him yes, I think it's the best universal iem, and he got confused asking what I meant... Opened a can of worms and almost lost a sale explaining to him what were custom iems.
And just two days ago, my co-worker sold HD800's to a rich chinese tourist who was looking for the "best" headphone. He was with three women who helped translate, and we had a hard time explaining to him they were open back headphones. He had noticed they leaked a lot of sound. He also found it wasn't loud enough, and when I showed him the Fiio E17, he was astonished that portable amps even existed; he assumed all headphones are made for ipods, really. I was surprised he ended up taking the headphone, he just wanted the best sound no matter what; I was going to recommend my co-worker show him the SE535's instead. He was using an app for his music, streaming.
So in my experience, many people who buy the highest end stuff, actually know nothing about it... People who spend between 300-1000$ are usually well educated and know the terminology and functions of different audio gear.
I'm sure many other sales people will say the same lol. People can be very strange with their buying behavior.