Why do bus drivers always wave at each other?

Driving a school bus typically means working alone. A bus driver is the captain of that ship all the time they're driving it. Sure, there may be other employees at the same business, but the separation of work space is verily evident.

In a sea of fast paced, high volume, rain or shine traffic situations, it's comforting to get a little wave of recognition from a fellow who shares your outlook on safety and defensive driving. A wave says, "I'm with ya, buddy!"