What I like about snaps is the spontaneous nature of them. A fan was there, the player was there, and usually there was an interaction between the fan and player that led to the photo being taken; the whole record of it is right there on the paper. They are sort of low-tech selfies. Here is a 1948 Durocher; you know there was a fan calling out to Leo to stand still for a photo:
They can also have a lot more personality than posed pro shots. The Cubbies on Catalina Island for spring training, doing a seven dwarves thing through Avalon:
Billy Cox outside Ebbetts Field. How often do you see a ballplayer now just walking into the stadium with the people?
Preacher Roe:
Ernie Harwell:
Joe Louis at a train depot in WWII; the photographer must've asked The Brown Bomber for a photo op:
Young Rocky Marciano at a training camp posing for the fan: