I was a teacher at a community college (may yet again be, but that's another story) and I went barefoot in my classes all the time. Also walked around outside, and in my office, sometimes walking out into the main office to the printer to get stuff. I usually wore (and wear) moccasins, so could kick them off easily. Oh, also at committee meetings I'd sometimes take them off so I could sit crosslegged in my chair. There were a couple other instructors who I saw barefoot in their office, and/or walking around in socks. I never quite pushed it to walking around the halls, but I was definitely known as the barefoot dude. Would have been interesting to see, if I'd obtained tenure, how far I could have pushed it. I'm sure the Dean and Prez would have hated it.
My favorite memories are of the times some, a few, of my students tried out going barefoot in class. I think I made a few converts.
Also, my sister used to work at Disney Animation, and would go barefoot all the time.
Here in Portland, I've heard some companies are fine with people bringing their dogs in to work. I can't see how they wouldn't also be ok with people going barefoot, but on the other hand there is a sort of weird prudery among the hipster elite.