Being of a (ahem) mature age, I do tend to gravitate toward sp's who are far younger, although not exclusively. Tboy's take on it was a bit direct, but I do see a certain strange logic to his statement.
Let's face it, for a lot of older men (I said older, not old), young women are a big thrill. Yeah, there is a certain mid-life crisis, red sports car, American Beauty banality to it, but it makes us feel like we still have something left in the tank, even if it is just pretend and just for an hour.