I was sitting at an outdoor cafe and having a conversation with a friend. I was in the middle of a sentence when a friend of his walked up, interrupted and started talking over me to him while totally ignoring me. The talked for about five minutes and the guy left. I just stopped talking and waited. When my friend finally turned his attention back to me, I just stared at him, then told him I was leaving. This has happened to me several times with different people. Why are people so rude?