I can't believe she did that. I feel sorry for you that you had to go through all that. Did your daughter notice the picture taking?
Maybe, however, you could use this as an opportunity to teach you daughter about inappropriate behavior in adults, rudeness, 'opinions' based on false information, and all those things people do. She's going to encounter those, and I think it might be good to talk to her about it, develop some sort of procedure. At the same time, it could be a good opportunity to ask yourself what your answer or attitude will be the next time an adult does something totally unacceptable, so that you will save yourself the energy and anger which I'm sure you felt, but are all wasted on such ignorant, vile people.