I work in tech support so yeah, I too have users anywhere from a few feet away, to waiting in the next room over (popping in from time to time to check up on things). Sure, I prefer to work alone in my office, but that just isn't possible most of the time.
I still think it would be nice to have the ability to look over your car while it is being worked on. I mean, it wouldn't have to be ALL bays, but maybe the ones doing alignments, oil changes, inspections, etc...I don't think anyone is saying they are going to sit there for hours on end while anything major is being done (although I can't say I wouldn't be tempted if I had nothing else to do that day...lol). I mean, even if it meant calling ahead by a few days to request "technician x" to work in "viewable bay x"...if you know what I mean...