Ha! Here's a shot I took of my lunch while on travel in Philadelphia. No great work of art, just wanted to document my first REAL cheesesteak sandwich. Well, it was selected as one of the shots representing the restaurant, Jim's Steaks, in an online travel guide. No compensation, just attribution (as per my creative commons license).
I imagine Flickr has become such a resource for sites like this, heck once Geotagging of images becomes more prevalent their job is even easier.
I used to think giving away images cheapens the art, but lets face it, photography has changed forever, equipment is more accessible, people are taking more images, and good images at that. Those that complain about it need to put less effort into complaining and more into improving on their art to separate themselves from the pack and give one a reason to pay for their work.