And I mean, old ones.
The idea goes like this:
Suppose you go to a flea market and buy a box of 100 photos for $100.
That's $1 per photo, yeah? Great.
Now, suppose that you spend $10000 for your website.
If you sell each photo for $5, you have $500. That's 5% of the price of the
website. Obviously, you need to sell a lot of photos to plow back the money and then go into the black (naughty people: nobody noticed it said "red" here?), but here is the thing: selling them WILL NOT BE DIFFICULT. A well placed Google AdWords campaign, some FB advertising and you can probably sell 1000 photos per day.
The rest is profit.