Well being from the South its just natural for me. I think it at the minimum says "Hey at lest I see you if none of these damn cagers do" If im in my car or pick up it usually just to people round the neighborhood or in my home town where its small and slow enough for people to acknowledge and return greetings, or passing by someone on an old country road. On highways and crowded streets only to other riders unless I'm giving someone the middle finger salute.
