In some cases, our audience might be one we have less control over. Paparazzi enjoy taking photos of celebrities while they are dresses poorly or without make-up. The existence of these pictures does not necessarily have a real impact on what we think about a person, but it captures ones perspective in a physical way; As Susan Sontag puts it, "It means putting oneself into a certain relation to the world that feels like knowledge." In this way, strangers who see pictures or videos of us are invading our privacy because they attain a feeling of knowing who we are when in reality, they do not and cannot. The sense of invasiveness intensifies when the images themselves are created by a stranger who captures and reproduces their own perspective of the subject.
Maybe we should not care what someone we will never meet could think when they see a picture of us, but people are naturally empathetic of opinions others have on them. Bad photos of ourselves provoke the same sense of discomfort as being told you are disliked. We have all taken a silly photograph in the past. The message one sends in such a picture is one of defiance, by breaking away from the photographers' or audiences' standards we tell them, "I don't care what you think of me." When pictures or videos are taken for their instrumental or functional value it can send a message of itemization.
While most people envy models who are photographed to market high priced clothes and other products, models for pornographic magazines are admired by very few. The undesirability of working in the porn industry is obviously more of a privacy and moral issue, but both of these industries receive a notable amount of criticism for how their images objectify and itemize their subjects. If a woman wears a revealing outfit she probably intends to be seen wearing, but photographing her without knowledge or permission would probably offend her as it could be seen as objectification of her body.