As a kid in the 1970s, I rode my bike everywhere, never wore a helmet (nobody did), and here I am today. Of course helmets can help avoid head injury, not riding bikes probably helps even more. I mean where do you draw the line on the fear vs. the actual chance of something happening.
On the subject of community shared bicycles, our town tried that about 10 years ago, all the bicycles were stolen within the first month (or maybe it was the first week) and it basically died at that point.
Survivor bias, perhaps? All those kids that died in the 70's from no helmets, falling out of pickups and going through the windshield of cars[1] aren't really here to say "I didn't make it."
I think we in the US tend to make things more scary than they really are in our efforts to protect ourselves from everything. However, I think the worst argument we can make is "I survived, so it is OK." There are good arguments that can be made for not wearing helmets, like how valuable it is to just get off your butt.
1. I am one of those kids (well, not the dead part). I managed to make it between the dash board and the solid metal mirror of a Volkswagon beetle from the back seat when I was four years old. A slightly different set of conditions would have had my skull turned inside out.
As a kid in the 1990s, I rode my bike everywhere, always wore a helmet (kids I knew did), and here I am today. Of course, my helmet may have saved me from serious injury or death when I fell from my bike while on a hill and landed on my head, cracking my helmet in two. I walked my bike back home, hurting but basically okay, happy that I wasn't allowed on my bike without a helmet.
Anecdotes are just a sample size of one and essentially useless... unless the population you care about includes that one person.
Conservatives often like to point out how "things were OK back in $DECADE" without these silly modern health and safety rules.
However that's not true. Less people are dying due to health and safety rules. E.g. The London 2012 olypmic stadium was the first olypmpic stadium that had no fatalities during construction.
On the subject of community shared bicycles, our town tried that about 10 years ago, all the bicycles were stolen within the first month (or maybe it was the first week) and it basically died at that point.