Haha that look on that guy's face is priceless!
I was at the market some weeks ago and as you, I also feel uncomfortable taking shots with people's face for this reason. I also don't appreciate it the other way around, so there's that. But then I found it hard to even take pictures without people so my pictures suck and I never made a market Friday post in the end.
Your pics look nice though! And I will take your tip and check out @dswigle's account, thank you!