Manipulation from peer pressure.
"My Jesus fish emblem is there to let everyone know that I am a devout born-again Christian. If you can't trust a fellow church member, who can you trust? Sign here and press hard."
I've used that one.
Back when I was in JROTC, we used to sell goodies door to door to fund trips such as 29 Palms, MCRD San Diego and Parris Island, and Camp Lajune, among others. There I would be in my short sleeve khakis, ribbons and a little gold cross that would stick out of my collar at the very tip. Sometimes, if I knew the person was a devout Xtian, I would tell them that I plan to use these trips to preach the word to my fellow cadets and Marines I met on the trips.
That's how I got my Civic Service Medal! Suckers!