One road trip yielded two catches and journal entries out of four releases - three were in Missouri, and I checked on the way home to see they were gone. One of those was journaled by "anonymous finder". Another book I left on a picnic table in a city park in Eureka Springs, Arkansas - a half hour later I drove by and it was gone. Several years later it was journaled after somebody bought it from a used book store in Harrison, Arkansas (maybe 75 miles away?) that coincidentally I'd bought books at on another trip to the area.
I would rather just RABCK, or meet with fellow BookCrossers to swap, or leave in an OBCZ (though I've had no journal entries from ones left at Panera Bread here in Des Moines or an Omaha coffee shop I always leave a book at whenever I visit there) or Little Free Library.
Once, when a girlfriend and I split up, apparently a box of books got left in her house. After she died in a car accident, her mother took all the books in the house and dropped them off with Planned Parenthood, and a few journal entries came out of that - one of them from Israel!