All The Gear, All The Time.
If you spend any amount of time actually observing motorcycleists, you'll see that even though riding a motorcycle is pretty dangerous (Statistics show that motorcyclists are 10x as likely to be involved in a crash as a car, and 16x as likely to die in a crash as someone in a car), there's a hell of a lot of people who don't feel the need to wear any protective gear. Or wear such comically little that it's really just for show. Weekend warrior Harley riders are famous for this: often refered to as "Pirates", or being "Pirated out", because their version of safety gear seems to involve a bandana, thin leather vest, blue jeans and fingerless gloves. In the states that do have mandatory helmet laws (lid laws), you'll see them wearing usually just a little half-helmet. How on earth those things got DOT certified, I've got no idea.
Squids/Stuntaz are even worse, especially here in the south I've seen. Tee-shirt, shorts, and flip-flops. Sometimes they'll have an insanely expensive Arai helmet or something, but no other gear at all. Seriously? On crotch rockets? I heard word from someone who had worked at a dealership for a while that the average lifespan of race-specced bikes (Like the Honda CBR 600RR) is less then 2000 miles. They're usually wrecked by that point.
I can't fathom this. I fall proudly into the ATGATT (All The Gear, All The Time) camp. Most of this is because I've seen videos and pictures of what they have to do to road rash in the ER, and then things like this: http://www.flickr.com/photos/roentgenator/2450912496/in/set-72157601198404570/ (a 3D X-ray of the results of crashing without a full-face helmet). And a fair amount of time spent reading the "Face Plant" section on Adventure Rider (http://www.advrider.com/forums/forumdisplay.php?s=&daysprune=&f=17) has made me notice a strange difference between posts that end in "So I should be okay in a few months" and "I walked away". That difference is usually the amount of gear that people were wearing.
I have two sets of riding gear, for different climates/weather. Currently, I'm wearing a Teknic Supervent Pro jacket, and Draggin' Jeans brand jeans, which are lined with 13-oz Kevlar in the hips and knee area. As well as armored riding gloves and my steel-toed and shanked Matterhorn work boots, I'm wearing a Nolan N-102 modular helmet. For cooler weather, I have an Olympia Phantom riding suit, which you've seen pictures of me in before. It's a brilliant suit, hard armor in the knees, hips, spine, sholders and elbows, as well as very tough and abrasion resistant Cordon reinforcing at all the bits I'm likely to slide on. It has plenty of vents, but due to it's windproofness it's not great for much above 80f.
Proper, high-quality riding gear makes being on the bike SO much more pleasent and enjoyable. I have no idea how people stand riding with no helmet or even an open-face helmet; the wind burn after a few hours would suck ass, and the wind roar would leave you deaf. And I would NEVER have been able to ride in the cold, wet, horrible conditions that I have gone riding in without that Olympia suit.
And then there's all the advantages of not even having a scatch or bruise on me after sliding across asphalt for 50 feet.
How people manage to get on a bike without the gear, I'll never understand.