Of all the various tracts I've ever read, none come close to the appeal of Chicks. My kids had a ministry they invented back in the 90s they called CHOW... Christian Homeless Outreach Workforce. They'd drive to a notorious homeless hangout public park location near downtown Phoenix AZ, stop the van and begin handing out hot hardboiled eggs, peanut butter sandwiches, hot cups of tea and Chick tracts to homeless folks. Sometimes it included donated blankets and coats when available, but it ALWAYS had to be Chick tracts.
Homeless people would line up when they saw the van pull up, all orderly and polite, and gratefully accept the food, then they'd find a curb to sit on and start reading the tracts and eating. Then, more often than not, they'd start swapping the tracts with each other so they could read as many as possible.
We purchased the sample package back then so we had a huge assortment, instead of all of one topic. For pretty much all our kids' growing up years I had a big basket full of Chick tracts in the living room and whenever my kids had friends over, there was always someone who wanted to just sit and read Chicks. I still have a Chick tract basket in my living room, in fact. Sometimes now it's grandkids and their friends who are reading them.