If I steal your car, two things are undeniably true:
- You don't have your car any more.
- I possess a car I have no particular right to possess.
There is a third thing, a corollary of the second item: I could mis-use your car in such a way as to make trouble for you. I could rob a bank and use your car as a getaway car, for example, leading the cops to your house for some probing questions. I can use your car in ways that you do not approve of, and since it's yours and not mine that's pretty much wrong, no matter what.
If I steal a song, it's true that the first item no longer applies. The second one most certainly does, however. It's unlikely that I can work out how to use an mp3 as a weapon, so the corollary might not apply. What if I played this copy of the song to provide a little soundtrack while I murdered someone? How would you feel about that? What if I stole your credit card number?
Susan Sontag asserts in On Photography repeatedly and correctly that Photography is an appropriative, aggressive, act. One takes a picture, there's no denying it. We can natter on about making it, and that's also true. We do make these things, there is a creative act. A photographer is an artificer. A photographer, however, is also a thief and a taker. When I take your photograph, you lose nothing, but I gain something. I have your image now, an image which I may or may not have any moral right to, which I may or may not have a legal right to.
What if I take a picture of the tree in your front yard? You still have the tree. I have made an image, through my labor (albeit trivial labor) I have made a sort of a copy of your tree. I possess this image. Most likely, you have no problem with my possession of an image of your tree. What if I make 10,000 images of your tree? Are you still comfortable? Oh, you're comfortable with the 10,000 images, it's my standing around on the sidewalk every day that creeps you out? I forgot to mention, I used an extremely high speed camera, and took 10,000 images of your tree as I walked past yesterday. It took 20 seconds, and then I left town never to return. I'm not a stalker, I just happen to have 10,000 images of your tree on my computer's hard drive.
What if I made 10,000 images of you as I walked by?
It is this, more or less, which makes the ubiquitous photographic theme of poverty and pictures of homeless people so problematic. The "information wants to be free" crowd would point out that the homeless guy has lost nothing. The thinking human beings among us will point out that the photographer has gained something. The photographer has an image, an image to which he or she has no particular moral right; arguments to the contrary boiling down to nothing more than a bald assertion of that non-existant right.
The corollary also applies. Even if the photographer's use is simply to post the photograph of the homeless guy on a tumblr blog or something equally superficial, it is entirely reasonable that the homeless guy does not want his image held up as an object of pity, of freakishness, of thank-god-thats-not-me-ness. We can pretend all we want to that we're just educating people about the true nature of poverty, but that's not true. Homeless guys are freaky and cool looking, and that's why we take their picture.