This is the guy who runs the Shroud of Turin website. On the "books" page he pushes several books you can purchase. People believing in the Shroud help him sell books for people. And what else does he get out of it? From his own biography:
"He has appeared in programs and documentaries on every major broadcast and cable television network, including the History Channel, the Discovery Channel, the Learning Channel, the National Geographic Channel, CNN, PBS, the BBC, Fox News, Channel 1 Russia, the Coast to Coast AM radio show, Catholic Answers radio and Vatican Radio. His photographs have appeared in hundreds of books and publications including Life Magazine, National Geographic, Time Magazine and Newsweek and in countless television documentaries. He has written many Shroud articles and papers that have been published in periodicals or presented at conferences around the world, the most recent in the March 2010 issue of Catholic Digest."
A religious motive AND a profit motive. Life Magazine, for example, paid fairly well.