I am one of those guys....
If you are not, there is no way you can understand. There is actually a "Need for speed", or at least a need for adrenlin that is common in more people than you may think. Most of my friends. I've broken 63 bones over the years doing everything from whitewater rafting to motorcycle racing, have been over 200 MPH in a car, and over 180 on a bike. I had a dirt bike that would top out at just a nick under 120 on pavement. Everone around here thinks I'm crazy too, but I can accept that. My brother and I raced trucks/buggys off road, won a championship in the CORR series and a 2nd in the WSORR series. I broke my back in a buggy in a practice accident, ended that for me but I still ran enduro for a few years.
That guy can ride a bike, him and I would probably get along just fine.