Latest Pet Peeve

So, here's the latest pet peeve.
Does no one remember the rules of sidewalk etiquette?? This TOTALLY DRIVES ME NUTS!!!
Samuel, my 7 year old, and I walk to school/work together every morning. It's a lovely time for bonding, chatting and such. Except for when I'm frustrated with the other walking public. When we started this routine at the beginning of school, I taught him that if someone was walking toward us, it is very important to SHARE THE SIDEWALK. He needed to either walk ahead of me or fall in step behind me until the person/people passed us by. It's only polite. We don't own the sidewalk, we ALL HAVE TO SHARE!!!
Apparently, walking public have changed the rules for walking together as a harmonized body. Old ladies walk down the middle of the sidewalk and don't move for nothing! Both of us end up scurrying off the sidewalk to let them pass. Teenagers assume I should walk on the road for them, so they can walk together, 3-wide, taking up WAY more than their share. There is one mother who walks with a stroller every morning, with about three other kids in tow. Do you think she would move to her side of the sidewalk with the darn thing so we can all share? Not on your life, buddy! The morification of this is that she is now training the other 4 or 5 children in her care, that it is unnecessary to be polite and share.
Samuel moves quickly and now without even a second thought to share the sidewalk. It's just what he does.
He's a good boy.