As someone who played a lot of quake in the day, I'll be the first to admit that bunny-hopping is an absurd-looking mechanic. However, a lot of people talk about movement mechanics in video games today, because movement should be one of the most dependable and flexible tools at your disposal in an FPS. Bunnyhopping added the extra nuance of being able to maintain speed, accelerate and strafe all at at the same time. If you mastered Quake's movement (namely bhopping and rocket jumping), you had an objective advantage over your opponent. Even if the other person had better aim, you still had the opportunity to out-maneuver them, which is something I seldom see inside modern video games.