I *try* to be an ambassador, by my actions, but sometimes, it feels hopeless. On my husband's drive/ride to work there is a large pack of cyclists every MWF. They ride in the middle of the road and never move. He is going to call the police. It's obviously a heavy duty training ride, but riders like that give us all a bad name.
Yes, people have seen my middle finger, too, even though I ride on suburban/country roads. On my commute home, it's often school buses that are the worst.