Stock Photos can be found all around the web, here at Deviant Art, with precise licences, or in Image banks like Getty, Fotolia or Shutterstock.

The huge price difference between Getty, for example, on one hand, and the "micro stock", which prices around 1 or 2 euro, is quite difficult to understand for Mr. Smith, and generates an overall feeling "Photographs are overpaid, and images should be for free, or nearly".

But actually, when you look into the general conditions of these stocks, you discover an astonishing point : the bank, which displays everywhere "Free of rights images" actually gives absolutely no warranty about that.

If, in any case, you would breach a copyright, by using, according to their terms, an image you bought on their website, they are not responsible.
If, in any case, somebody would use one of your image, sold by somebody else through the Bank, they would not be responsible.

But they are the vendors.

One of them, Fotolia, even tries to place all its transactions, worldwide, under NY law.
I don't know about NY law, and I don't know whether it is legal or not to force all transactions as being "between professionals", but I know that in Europe, this is not legal.
I know that, at least in Europe, a professional is really one, and not a private person who buys on a website one image for his blog.
I know that, in most European countries, the private customer is protected, and for example, can decide to sue a Bank in front of a European court, because he is a private person.

I also know other online banks, which do not exonerate themselves from their responsibilities. And, strangely, the price suddenly increases, we are not speaking anymore of 1 to 3 euro, but 50 to 200.
Because making sure you are allowed to sell what you sell, and taking responsibilities for that means checking upfront, managing, and that implies much higher operational costs.

DeviantArt is really an intermediary. When I take here a Stock Image, I download it from the page of the photographer, I see his terms, and when I don't follow them, he will sue me. And DeviantArt, though being just an intermediary, tries to do its best to protect our rights.

"Expensive image banks" are also protecting me, either as a photographer, or a customer.

Cheap ones... well, I don't really know what they sale. I have a friend who bought images by Fotolia, and was they sued by the real owner of the rights, and had to pay more than 1.000 euros (1.500 USD) to him. That is what a 1 euro photo can cost !

There are more details on my blog, about how Fotolia is not applying the law, but this is in French only...