I heard a great quote once...They're two types of people in the world, those who think there are two types of people in the world,...and those that know better.
I do think there are two types of bikers. Not motorcycle riders; bikers. BMX, mountain bike, ten speed, etc...
First there is the man/woman who rides because he/she wants to ride. They've got the gear, the bright yellow spandex jersey with the padded crotch. Matching streamline helmet. The special shoes that clip in to their pedals so they can maximize every up and down stroke. Two water bottles full of Vitamin water. Ipod strapped to their arm with the cord neatly tucked through their spandex. The blinky red light on the back, and the blinky headlight on the front to warn motorists of their coming or going. These folks are usually in shape, calves that could stunt double as horseshoes and thighs that could crush walnuts. They look like they know where they're going and how fast they're going to get there.
Second type: A little aged (25-40), dressed in everyday apparrel, no bike accessories, usually on a BMX style bike. These guys are not riding a bike because they want to. They are riding because they have to. I'm guessing it's because of their choices... Is it me or do these guys kind of just troll around, not really heading anywhere in particular. They just kind of bump around streets and parking lots and business areas. They have a shifty way of looking around, like they're looking for some type of opportunity, for what I don't know... Anyway that's only my point of view and my observations.