[TOMT][short story] A short story about parallel universes

About a decade ago, I remember reading a short story in a book. The narrator was working at a roadside diner in the middle of nowhere, and he talks to one of the customers. The customer explains that he travels between universes for fun, having a device that takes him to a random one each time. For example, one was where Napoleon won the Battle of Waterloo. There are many other that do this. The problem, however, is due to the chances involved, the probability of returning to your original universe is infinitesimal; there will always be something different.