I was at a conference recently and 4 of us conference-goers were sitting at a table chatting. These are three good guys so I got up to snap a picture - and one of them nearly fell over backwards trying to push his chair back, so he'd be out of the picture. I've never seen anyone that horrified to be photographed. The funny thing is, if I'd been doing it discreetly I'd probably got the picture.
What is so horrifying about being photographed? I do understand you can try to avoid being photographed. Some people do. But you simply can not escape it. Too many security cameras all over the place.