I like to draw parallels between cycling and other activities.

There are some people that wear a helmet for EVERY bicycle ride and some of those people go out of their way to tell other cyclists that they're stupid or crazy for not adhering to their protection level requirements. There are not many other activities that have such a large number of participants that take such a tough stance on protection levels. Some ice skaters wear helmets for some applications but almost none wear one for every skate session. Same for skateboarders. Same for trail runners (here almost none wear helmets.) Same for skiers.

Very odd, if you ask me.