"why do we preserve baseball memories with such meticulous care, yet fail to preserve where the founder of baseball fought and gained his place in history?"
Retarmy, I presume you are talking about General Abner Doubleday and Morris Island. Contrary to legend, Doubleday was NOT the founder of baseball, "gained his place in history" (if at all) at Gettysburg, and didn't have anything to do with Morris Island (he served at Fort Sumter, instead).
Perhaps I should have written: Why does American culture hold sports, sporting figures, and sporting venues in greater regard than the heroes, hallowed places, and the history that shaped American society?