I was thinking about this today when I rode the first "real" bike in my life.
My Huffy monoshock was just as cool when I was kid. Even cooler than the kid next door who had Ashtabula forks on a Kawasaki BMX bike. Later I got a 10 speed Schwinn and beat him in a race. I ground away my jeans down one leg and got horrible road rash from knee to ankle. I ground off a dust cap on one pedal on that one.
We rode our bikes everywhere, year round and all of us had at least one pair of jeans with chainring holes in one leg. No one wore a helmet, sometimes we didn't even wear shoes. We built our own BMX track in a vacant lot.
I don't see many kids out on bikes today. They're missing out.