Sport bikes/crotch rockets may be geigh but they are like sports cars. More control.
Precise throttle control effects cornering on a bike way more than it does in a car. A near 50/50 weight distribution (hands/feet as well as front/back wheel) gives you a better road feel... pretty important if one of the wheels begins to slip in a corner. Putting weight on the handle-bars also gives you a much shorter reaction time, when Granny cuts-you-off. Besides, once you're moving the wind can hold your weight, if you want it to. Sport bikes are also taller which gives you a better view of traffic.
Not that I wouldn't wanna harley boat anchor......just sometime after 45 when your balls supposedly fall off.