What we have here is a signal-to-noise problem. Humans evolved brains that are pattern-recognition machines, adept at detecting signals that enhance or threaten survival amid a very noisy world. This capability is association learning--associating the causal connections between A and B -- as when our ancestors associated the seasons with the migration of game animals. We are skilled enough at it to have survived and passed on the genes for the capacity of association learning.
Unfortunately, the system has flaws. Superstitions are false associations--A appears to be connected to B, but it is not (the baseball player who doesn't shave and hits a home run). Las Vegas was built on false association learning.
Consider a few cases of false pattern recognition (Google key words for visuals): the face of the Virgin Mary on a grilled cheese sandwich; the face of Jesus on an oyster shell (resembles Charles Manson, I think); the hit NBC television series Medium, in which Patricia Arquette plays psychic Allison Dubois, whose occasional thoughts and dreams seem connected to real-world crimes; the film White Noise, in which Michael Keaton's character believes he is receiving messages from his dead wife through tape recorders and other electronic devices in what is called EVP, or Electronic Voice Phenomenon. EVP is another version of what I call TMODMP, the Turn Me On, Dead Man Phenomenon--if you scan enough noise, you will eventually find a signal, whether it is there or not."
Here is the famous Virgin Mary on a Piece of Toast that Shermer mentioned;