I have seen three adults in headgear in public that I can recall, but all were a long time ago.  One was a man who was about 20 in cervical headgear on a college campus, another was a female in a café in highpull headgear with j-hooks, and another was a female in her 30's wearing cervical gear in a department store.  All three of these were in the late 1970's/early 1980's.

I haven't seen someone my own age or older wearing headgear in public since I was 14 in the 90s. From time to time I would see it on kids, but after that point, never anyone older and never on an adult at any point.

i never see it in Hong Kong...

Never. But I've also never seen **anyone** wear headgear out in public IRL, so...

I feel like if I ever did see someone, it would take everything in me to not stare.

Would like to do it myself ... need to get over the inhibition :-)

Same  here, wore my HG in public in a supermarket. And had to wait in a long cue before the cashier, next to the entrance.
Have to say i was gathering guts in the car before entering.

I just loved the feeling

the feeling i have afterwards is more like,,, why did i not dare to do this...