Analyzing scientists at a meeting: 4 of 5

Written 10/1/08, posted later
This is the fourth post from the grant agency meeting.

Why is something considered unprofessional in a young scientist seen as funny or charming in an older scientist?

Why is disrespectful behavior more tolerated at a meeting than in a classroom? I've heard conversation that makes it difficult to hear the speaker and cell phones ringing, sometimes quite loudly. Many people (like me) have been using laptops during talks, and I doubt they are all taking notes on the talks. It is regular practice for a scientist to finish a talk at a meeting during another scientist's talk.

I realize that there is some difference between professional meetings and classes, but why is there such a divergence in manners? A teacher would never tolerate a ten-minute quiet-down period at the beginning of a class.

Such conduct also makes me wonder if these scientist respect each other equally or if there is a hierarchy (either well-defined or varying by person).