That does bring up a good side point, I see many riders with boots, gloves, jackets, and helments but regular jeans (no draggon jeans).
In addition to skin loss, a bit of padding on/around the knee may make a lot of difference, depending on how you go down and end up at a stop. There's nothing to prevent everything but a little insurance is better than none for saftey.
A extreme that always gets my attention is the person in shorts, tee shirt, gym shoes and the coolest $400 plus sunglasses. Sometimes this person comes with a passenger on the back dressed the same. I don't get taking someone elses life into your hands with little to no concern.