an exercise in futility?

In my mom's family, the youngest daughter was named Isabelle.
The family had a Knock Knock joke that went like this:

Knock, knock
Who's there?
Isabelle.
Isabelle Who?
Is a bell necessary on a bike?

Well, if you ride in Edmonton, the answer to that question is YES. Until recently, however, I didn't realize that the law goes a little further: you must have a bell on your bike, and you must ring it when passing pedestrians.

Since learning that, I have tried to comply, faithfully ringing my bell to warn pedestrians of my approach. Some people react by jumping into the air or moving off the trail onto the grass, as if they're afraid I'll hit them otherwise. I always say a gracious thank-you, but I do feel bad for seemingly inconveniencing them. My favourite people are the ones who, upon hearing the bell, stay to the right, continue walking and calmly raise a hand to let me know they are aware of my presence.

Other pedestrians are a little more difficult. Some, especially those who walk in groups of three across the whole path, seem to be downright deaf and continue strolling along as if they are the only people in the world. Others, with earphones in place and music blaring, are clearly oblivious to my existence. People like this make me wonder whether my bell is any use at all.

The ultimate "makes me wonder" story was when I encountered a group of school girls on the multi-use trails here in town. There were about 10-12 of them, and their walk was clearly a class outing of some sort. They were talking and laughing and having a good time, but were blocking the entire trail. As I approached, I rang my bell a couple of times. No reaction. I slowed down and rang it again, louder and repeatedly. Still no response. I slowed even more, rang the bell again and called out, "Passing on your left." Still nothing. Finally, when I was right behind them, I yelled at the top of my voice, "Girls! Move over!" and at last they complied. But as I rode past, one of them had the nerve to say, "Hey lady, you should get a bell on your bike."