America's so-called mega churches, while damning the Internet to hell for its porn and smut, are the biggest buyers of low-priced online stock photography and video.

iStockphoto, now owned by Getty Images, is set to double its revenues next year to about $US140 million ($166 million). It uses 65,000 mostly amateur or part-time photographers who snap images, upload them and then receive a fee each time they are bought by businesses or individuals not wanting to pay a fortune to use pictures taken by a pro.

The company sold 18 million photos, illustrations and videos online last year and apparently the mega churches in the U.S. burn through an unbelievable amount of content. This is because they use mammoth projection screens and everything is totally multimedia, with video as well now in every section of a service.