Trying to run down the "Hoot and Annie" story. It may be just a story. I have found two wives for Hoot, neither one of them Annie. I know I heard the story from my parents a long time ago, so it has been around for some time.
Hoot Gibson war World Champion Cowboy at Pendleton in 1912 and World Champion Roper at Calgary the same year, then went on to Hollywood. His first good role came in John Ford's first feature, "Straight Shooting" in 1917. After 1920 he became a Universal star. He divorced his first wife Helen; can't find his wife in the 1920s, if he had one. There was another in the 1930s, also not Annie.
The word is supposed to have originated on the west coast, but no real evidence. It could have come from the Midwest area where Pettus found it.