There was a popular book years ago called "All I Really Need To Know I Learned in Kindergarten." Lessons included how to share, how to wait your turn and how to line up without touching the guy in front of you.
Rudeness and bad manners - and books about them - are on the rise. Technology clearly has much to do with this. Even "smart" technology has made many of us seem "less smart." (That's a polite way of putting it.) It's certainly made people more distracted and self-centered, both of which breed bad manners.