Sidewalk Etiquette

This is something that has been bothering me for a while now and I'm going to go on a little rant. I've noticed recently a glaring lack of regard for the rules of sidewalk etiquette. There are some very basic unwritten rules when using a sidewalk.
1. Always stay to the right side unless passing. This allows for maximum traffic flow, and leaves room for faster walkers to pass slower ones. 2. Never walk shoulder to shoulder with a friend on a normal width sidewalk. This prevents faster people from being able to pass and can cause various emotions of a negative sort to be released. If you must talk with someone, the right most person should walk off the sidewalk to allow room for passers. If there is no room to walk next to the sidewalk, simply discontinue the conversation and move into single file. Under no circumstances should three people attempt to carry on a conversation or walk together while using a sidewalk.
Now I've noticed these rules being broken quite a lot in my travels between classes on campus. You're late for class and there a big group of friends walking slowly along, blocking the whole sidewalk and preventing you from being able to pass and get to class on time. You show up late, the prof gets angry, you are already angry and the whole situation goes downhill fast. Your whole day is ruined single-handed by a group of rude people.