Some people just won't wear a hardhat, no matter the rules or instinct for self preservation. On the other hand, maybe if they start young it's a different story, that's how it worked for me - 15 yrs old, shoveling the deep snow around trees so dad could make low stump cuts - "Here boy, wear a hardhat, this is dangerous, AND it's the law".
So I'm driving along and see this kid trying to jump up and grab a hanging branch but can't quite reach. I stop, grab my brain bucket and pole hook, I say to him -"Let me help, I hate to see anyone doing treework without a helmet". "Wait!" he yells, and RUNS into the house, 20 seconds later he's back wearing a "Real" hardhat.
His enthusiasm really blew my mind after working with guys on the OSHA regulated timeclock who practically refuse to wear one and when asked if they have one say "I'm not even sure where it is" - wierd phenomenon.
So treeclimber is referring to the pic you attached to your 1st post of you in the bucket with a bare head.