As was at my local LBS talking with a few of the employees about things that are different today than they were in the 70s when I started riding. I pointed out that in the 70s when you passed another rider you always acknowledge him or her with a slight hand wave or nod of the head. I said that yesterday I passed three other riders, did a slight wave and head nod to all three with no acknowledgment from any of them. The youngest guy in the shop says, "That's 'cause rude rules." He went on to give his version of why acknowledgement of another rider was not cool. So, does rude rule? If so, what's happened in the last 30 years?