I can think of another reason. This applies to bicycles in general. But that includes motorized bicycles. It's exhilarating to go out and defy any weather that Mother Nature chooses to throw at us. I usually win, too. It's very rare for me to be out riding and thinking, "ooohh....I shouldn't have done this". I don't think it's happened at all for a few years. There are all sorts of days that I watch my colleagues walking out to their cars almost in tears over the cold rain, the freezing wind, etc. Usually I'm thinking, "Hey! This is all right". Most of the folks around me have no idea of the feeling of well-being to be found by merely embracing the outdoors whatever it happens to be like that day.