Not wanting to spend money on it is understandable. But watch it online, and not just that scene. You cant get a feel for what kind of movie and humor it is without the whole thing.

Knocked up had a scene in which the woman is drunk (and so is the man) resulting in a baby. That's a very different kind of humor than this one.

None of the reviews I read even make reference to the scene, so it must not be remarkable in comparison.